Oh, you know those moments when you just need a hug in food form? For me, that’s always been about chocolate and peanut butter swirling together. These Peanut Butter Thermomix Brownies aren’t just a recipe; they are straight-up childhood nostalgia wrapped up in a warm, fudgy square. My grandmother used to swirl peanut butter into her batter “just for fun,” she’d say, and those marbled trays were my absolute favourite after school.
When I started Sena Recipes, I needed to capture that cozy, homey feeling but make it fit into our hectic modern lives. That’s where the Thermomix comes in! Trust me, it melts the butter perfectly and gets the base batter silky smooth without any heavy lifting. I still remember the first time I tested this batch—lifting the lid brought back the exact smell of cocoa and creamy peanut butter from her kitchen! Seeing those beautiful, imperfect swirls on top always feels like a little bit of baking magic.
This traybake is straightforward, reliable, and honestly, it delivers the richest chocolate texture you can imagine, perfectly balanced by that salty PB ribbon. It’s the ultimate comfort food, made simple.
Why You’ll Love These Peanut Butter Thermomix Brownies
- The texture is unbelievably rich and fudgy—pure chocolate heaven.
- Using the Thermomix makes the mixing process almost entirely hands-off and super fast.
- That classic flavour combination of deep cocoa and creamy peanut butter swirl is just unbeatable comfort.
- It’s a brilliant traybake that cuts cleanly, making it perfect for sharing with friends or family. If you love this combo, check out my Banana Bread Brownies too!
Honestly, these simple bullet points don’t even cover how satisfying this bake is. Trust me, you won’t want to skip this one!
Essential Ingredients for Perfect Peanut Butter Thermomix Brownies
Okay, let’s talk about what you need. Since we are relying on the Thermomix to do the heavy lifting, we need the right stuff in there to handle that heat and mixing power. Don’t skip on anything here; these ingredients work together beautifully!
For the brownie base, you’ll need 150 grams of butter, which you should cut into cubes so it melts easily in the machine. We use 220 grams of caster sugar for that delicate sweetness, alongside 75 grams of rich cocoa powder. Three good eggs are vital for structure, and 75 grams of plain flour keeps things simple and classic. Don’t forget that little splash of 1 teaspoon of vanilla extract—it just makes chocolate sing!
And for the star of the show, the swirl component, you need 200 grams of your favorite peanut butter. Use something creamy, a standard jar variety works wonderfully here; we don’t want anything too runny.
Equipment Needed for Your Peanut Butter Thermomix Brownies
You don’t need a mountain of fancy stuff for this recipe, which is part of why I love it so much! Since the Thermomix handles most of the heavy lifting, we keep the other tools basic.
First up, obviously, you need your trusty Thermomix, because that’s doing the melting and mixing for us. Make sure you have the standard mixing bowl ready to go. Secondly, you’ll want a sturdy 20cm square baking dish. Make sure this is greased really well, or lined with parchment paper—otherwise, those fudgy edges will try to stick!
Finally, for checking if these beauties are done, you’ll need a thin skewer or even just a clean toothpick. That’s it! No stand mixers or fussy gadgets required here, just good old reliable kitchen gear.
Step-by-Step Instructions for Peanut Butter Thermomix Brownies
Now for the fun part—watching your Thermomix weave its magic! This method is so quick that you’ll have a traybake ready for the oven before you can even decide what to watch on movie night. Remember, precision on the settings is key to getting that decadent, fudgy texture we both look for in a great brownie.
Preparing the Oven and Dish
First things first, get your oven preheated to 160 degrees C (that’s fan-forced, just how the recipe likes it!). While that’s warming up, you need to prep that 20cm square dish by greasing it lightly and lining it—this ensures a clean lift later, I promise!
Melting Butter and Cocoa in the Thermomix
Time to wake up the machine! Place the cubed butter, caster sugar, and your cocoa powder right into the Thermomix bowl. Set it to go for 3 minutes on 65 degrees at speed 2. Once that’s done, give it a quick check; if your butter is stubborn and hasn’t fully melted in, just pop it back in for one more minute at the same settings. We want it fully liquid and smooth before adding anything else!
Combining Wet and Dry Ingredients for the Brownie Batter
Once the base is melted and lovely, you can easily add the vanilla extract, the three eggs, and the plain flour right on top. Mix this all together for just 10 seconds on speed 4. Seriously, watch the clock! Then, scrape down the sides—this is important to make sure everything is incorporated evenly—and mix for another quick 10 seconds on speed 4. Don’t overmix this part; we are keeping things fast and smooth.
Creating the Signature Peanut Butter Swirl
Gently pour all that beautiful brownie batter from the Thermomix bowl into your prepared dish and use a spatula to smooth the top lightly. Now for the showstopper! Drop spoonfuls of your 200g of peanut butter evenly over the surface. Take a butter knife—nothing fancy, just a normal table knife will do—and gently go through the batter, swirling the peanut butter a little bit. You don’t want to mix it completely; we want ribbons! This marbled look is what makes these brownies feel so special and homemade.
Baking and Testing Doneness for Peanut Butter Thermomix Brownies
Slide that tray into the preheated oven and set your timer for 30 minutes. Keep an eye on them! The goal for a perfect texture is usually between 30 to 35 minutes. You’ll know they are exactly right when you insert a skewer near the center and it comes out clean; this means the fudginess is set but still moist. Take them out, let them cool completely, and then you can cut them into tidy squares!
Tips for Perfect Peanut Butter Thermomix Brownies
Even though the Thermomix makes this recipe wonderfully straightforward, there are a few little secrets I’ve picked up over the years—things I learned watching Grandma and through my own baking tests—that really bump these brownies up from good to absolutely unforgettable.
The way you handle the peanut butter swirl is everything. Remember, we aren’t fully mixing it in! You want those distinct ribbons of salty-sweetness against the rich chocolate. If you mix too vigorously, you end up with just a slightly flavored brownie, not the beautiful marbling we want. Keep it light when you drag that butter knife across the top.
Also, cooling them down properly is a must, even though it’s so hard when they smell amazing coming out of the oven. Fudgy brownies like these need time to set their structure. If you rush to cut them while they are still warm, they will just collapse right off the knife and turn into a gooey mess—and nobody wants patchy, uneven squares! Let them cool fully in the pan before slicing for those clean, satisfying cuts.
And here’s a little something I discovered when trying to replicate that nostalgic flavour perfectly: if you have any good quality dark chocolate flakes on hand, sprinkle just a few small pieces over the batter before the peanut butter swirl goes on. It adds little pockets of intense chocolate that melt during baking and make the final texture even more luxurious. It reminds me of the special extras Grandma used to sneak into our chocolate treats!
Ingredient Notes and Healthy Variations for Peanut Butter Thermomix Brownies
I get asked all the time if you can swap things out in these rich brownies, especially since so many of my readers are looking into Thermomix Recipes Healthy options these days. For the peanut butter, feel absolutely free to swap it out for almond butter or sunflower seed butter if you or a family member has a nut allergy! It gives a slightly different flavour, but the texture benefit remains.
If you’re trying to lighten this up a bit—because sometimes we all need that—caster sugar can be substituted with coconut sugar cup-for-cup, though the colour will definitely deepen. For the flour, you could try swapping half of the plain flour for wholemeal or almond flour, but just be aware that it might make the final bake a touch denser since we rely on that structure!
Remember, these are still decadent brownies, but small swaps can make them fit your needs, keeping that wonderful comfort feeling!
Storage and Make-Ahead Instructions for Your Brownies
One of the best things about a good traybake like this is that it tastes even better the next day—if they last that long, that is! Since these Peanut Butter Thermomix Brownies are so wonderfully rich and moist, storage is really easy, which is great if you’re planning things ahead for a party or just don’t want to bake every single day.
Once they are completely cool—and I mean fully cooled down, otherwise you’ll get condensation in the container—you can store them in a proper airtight container. We usually keep them right on the counter at room temperature. Honestly, if you don’t have crazy hot weather, they’ll stay perfectly fudgy for about three to four days. The high fat content in the peanut butter and butter really helps keep them soft.
If you’re making a huge batch, freezing is an absolute lifesaver. You can wrap individual squares tightly in plastic wrap, then pop them into a freezer-safe bag or container. They freeze beautifully for up to three months. When you need a quick treat, just pull one out about 30 minutes before you plan to eat it, and it thaws perfectly back to that fudgy texture. This is such a relief when you need a quick treat later in the week for the kids, much like how I prep my make-ahead breakfast casseroles on a Sunday!
I never really “reheat” them, to be honest, because I love them cold or room temperature. But if you want that just-baked gooey warmth, zap a square for about 10 to 15 seconds in the microwave. Just don’t go too long, or the peanut butter swirl starts to get oily!
Serving Suggestions for These Comforting Peanut Butter Thermomix Brownies
Honestly, these brownies are so rich and flavourful, they seriously don’t need much more than a plate and maybe a napkin! They are phenomenal all by themselves, especially when you catch that perfectly gooey edge piece.
But, of course, if you’re piling these high for a proper dessert moment, you absolutely have to serve them warm—or at least room temperature—with a gigantic scoop of really good vanilla bean ice cream. The contrast between the cold, creamy ice cream hitting that warm, dense chocolate brownie is just heavenly. The ice cream melts right into those peanut butter pockets, too. Wow! It turns this simple traybake into something fit for company.
If you need something warm on the side to cut through the richness, a tiny drizzle of homemade caramel sauce is dreamy, or a simple dollop of cream works wonders. If you’re enjoying these as an afternoon treat with your coffee, try pairing them with something light, like a simple vanilla sauce you might use over a bread pudding, just to dip the corner into. It keeps things elegant but totally homey. Enjoy every single bite!
Frequently Asked Questions About Peanut Butter Thermomix Brownies
I always get a flood of questions after I post a recipe that involves the Thermomix, because everyone wants to make sure they get that perfect, nostalgic result, just like Grandma’s original! Dealing with questions about texture, tools, and kitchen adjustments is just part of sharing these kitchen recipes with you all.
Can I make these Peanut Butter Thermomix Brownies without a Thermomix?
Oh, absolutely you can! I developed this recipe specifically for the speed and ease of the Thermomix, but I know not everyone has one yet. If you’re using a regular saucepan, you’ll just need to melt the butter, sugar, and cocoa over low heat gently on the stovetop until everything is smooth. Then, you’ll transfer that mixture to a large bowl to mix in the eggs, flour, and vanilla manually with a whisk. It takes a bit longer and requires a bit more muscle, but you’ll still get a wonderfully rich brownie—it just won’t have that identical, super-silky texture the machine provides for the base batter.
Why are my brownies dry instead of fudgy?
That’s the absolute worst feeling, isn’t it? Dry brownies usually point to one of two things in this rich recipe. Most often, it’s just overbaking. These bake fast because of the fat content, so if you leave them in for even five extra minutes, they dry out fast. Always use that skewer test! Also, double-check your ingredient ratios—if you accidentally added too much flour or not enough butter, the balance is off and they will be cakey instead of fudgy.
What is the best way to get clean slices?
This is my number one tip for presentation that I share in my guide to Thermomix Recipes Healthy bakes too: Patience is key here! You MUST let the brownies cool completely in the baking dish before you even *think* about slicing them. If you try to cut them warm, the fudgy texture just collapses and squishes out under the knife. Once they are totally cool, even slightly chilled from sitting in the fridge for 30 minutes, the squares will cut cleanly with a long, sharp knife that you wipe between cuts.
About the Author: Emma Laurent and Sena Recipes
Emma Laurent is the Founder & Creative Director of Sena Recipes, where she shares comforting classics with modern flair. Her approachable recipes inspire thousands of home cooks to rediscover the joy of everyday meals.
Growing up in a family where the kitchen was the heartbeat of daily life, Emma learned early on that food is more than sustenance—it’s memory, comfort, and connection. In 2019, she founded Sena Recipes to share the approachable meals that combine her grandmother’s wonderful traditions with her own modern touch. She recognized that too many online recipes were either overly fiddly or just plain uninspiring, and she set out to fix that by creating dishes that are reliable and packed with flavour.
Emma’s signature style is serving up that deep sense of comfort food you remember, but with a simple, modern twist that means you can actually fit it into your busy week. You can learn more about her approach to cooking and family life over on her author page at Sena Recipes. We keep things joyful, simple, and always delicious here!
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Peanut Butter Thermomix Brownies
- Total Time: 45 min
- Yield: 9 servings 1x
- Diet: Vegetarian
Description
Make rich, chocolate brownies with creamy peanut butter swirls using your Thermomix for a simple, comforting dessert.
Ingredients
- 150 grams butter
- 220 grams caster sugar
- 75 grams cocoa powder
- 3 Eggs
- 75 gram Plain flour
- 1 teaspoon vanilla extract
- 200 grams peanut butter
Instructions
- Preheat your oven to 160 degrees celsius (fan-forced).
- Grease and line a 20cm square baking dish.
- Place the cubed butter, caster sugar, and cocoa into your Thermomix bowl. Cook for 3 minutes, 65 degrees, speed 2. If the butter is not fully melted, cook for an additional 1 minute, 65 degrees, speed 2.
- Add the vanilla extract, eggs, and plain flour. Mix for 10 seconds on speed 4 to combine.
- Scrape down the sides of your bowl and mix for another 10 seconds on speed 4.
- Pour the batter into the prepared dish and smooth the surface gently.
- Add the peanut butter in dollops over the top. Use a butter knife to swirl the peanut butter through the brownie mixture.
- Bake for 30 to 35 minutes, or until a skewer inserted into the center comes out clean.
Notes
- This recipe is inspired by childhood memories of marbled peanut butter brownies.
- The Thermomix helps achieve a smooth batter texture quickly.
- Swirling the peanut butter creates a beautiful, homey presentation.
- Prep Time: 10 min
- Cook Time: 35 min
- Category: Dessert
- Method: Baking
- Cuisine: American
Nutrition
- Serving Size: 1 brownie square
- Calories: 350
- Sugar: 30
- Sodium: 150
- Fat: 22
- Saturated Fat: 8
- Unsaturated Fat: 14
- Trans Fat: 0
- Carbohydrates: 35
- Fiber: 2
- Protein: 7
- Cholesterol: 70
Keywords: Peanut Butter Brownies, Thermomix Brownies, Chocolate Peanut Butter, Easy Brownie Recipe, Comfort Baking, Traybake, Kitchen Recipes