Hot Chocolate Brownies - Easy dark chocolate brownies that are fudgy and chewy, with sweetened homemade marshmallow fluff on top!

If there's one thing that screams its cold in January and want something to warm me up... it's these Hot Chocolate Brownies. They're rich, deeply chocolatey, and finished with swirls of homemade marshmallow fluff, which feels like a very reasonable life choice. After retesting this recipe, I made a few small tweaks to improve the texture and make the results more consistent! It's basically hot chocolate, just baked and cut into squares.
If chocolate with a little extra personality is your thing, you'll also love my Greatest Brown Butter Brownies Ever and Chocolate chip cookie bark which confirms I have a type and it's chocolate plus nostalgia.
Why You'll Love This Recipe
- Chocolate-forward in the best way - These brownies are rich, fudgy, and not interested in being subtle.
- That crackly top everyone cares about - Yes, it's there. No, you don't have to stress about it.
- Marshmallow fluff = hot chocolate energy - The topping makes these feel nostalgic without being childish.
- Tested, tweaked, and reliable - Because brownies shouldn't be a surprise.
- Easy to dress up or eat straight from the pan - Both are valid choices.
Ingredients - Hot Chocolate Brownies
Here's everything you'll need to make your brownie batter! Simple ingredients, no surprises. For the full instructions, please refer to the recipe card below!
- Granulated sugar - Essential for sweetness and that shiny, crackly top.
- Brown sugar - Adds chewiness and keeps the brownies fudgy.
- Large eggs - Use them at room temperature so the batter comes together smoothly.
- Egg yolk - Extra richness for a more decadent brownie.
- Unsalted butter - You will use melted butter. If using salted butter, skip adding extra salt.
- Dark chocolate - Brings deep chocolate flavor. A good-quality bar makes a noticeable difference. You can also use bittersweet chocolate!
- Vegetable oil - Keeps the brownies soft and fudgy for days. Any neutral oil works here.
- Vanilla extract - Rounds out the chocolate flavor.
- All-purpose flour - Just enough to give structure without drying the brownies out.
- Unsweetened cocoa powder - Boosts the chocolate flavor. Dutch-process works especially well.
- Cornstarch - A small amount keeps the brownies tender and soft
Step-by-Step Instructions - Brownie Recipe
Here's how you make these Hot Chocolate Brownies. For a full list of instructions, check out the recipe card below.
- Preheat the oven. Heat your oven to 350°F (175°C). Line an 8×8-inch metal baking pan with parchment paper, leaving an overhang on two sides. Lightly spray and set aside.
- Melt the chocolate. In a medium saucepan over low heat, combine the butter, vegetable oil, and chopped dark chocolate. Stir constantly until mostly melted, then remove from heat and continue stirring until smooth. Whisk in the cocoa powder until glossy. Let the mixture cool until warm, not hot.
- Whip the eggs and sugar. In a large bowl of a el, beat the granulated sugar, brown sugar, eggs, and egg yolk on medium to medium-high speed for 3-4 minutes, until pale, thick, and glossy.
- Combine the mixtures. With the mixer on low speed, slowly pour the warm chocolate mixture into the egg mixture and mix just until smooth.
- Add the dry ingredients. Gently fold in the flour and cornstarch until just combined. Stop as soon as no dry flour remains.
- Bake. Pour the batter into the prepared pan and smooth the top. Bake for 22-26 minutes, until the edges are set and the center is slightly soft. A toothpick should come out with thick, glossy crumbs.
- Cool. Let the brownies cool completely in the pan before topping or slicing. They'll finish setting as they cool.

Common Mistakes When Making Hot Chocolate Brownies
- Not whipping the eggs long enough. This step matters. The eggs and sugar should look pale, thick, and glossy-if you stop too early, you'll miss out on that crackly top.
- Adding hot chocolate to the eggs. If the chocolate mixture is too hot, it can cause the batter to look separated or greasy. Let it cool until warm, not steaming.
- Overmixing the batter. Once the flour goes in, be gentle. Overmixing leads to tough brownies, which is not the goal here.
- Overbaking. A clean toothpick is not what you want. Pull the brownies when the center still looks slightly underdone and the crumbs are thick and glossy.
- Cutting too soon. I know it's tempting, but warm brownies haven't finished setting. Let them cool completely if you want clean slices and the right texture.
Tips and Tricks - Hot Chocolate Brownies
- Use room temperature eggs. Cold eggs don't mix as smoothly and can affect the final texture. Let them sit out for a bit-it helps.
- Measure the flour carefully. Too much flour will turn these brownies dense. Fluff, spoon, and level, or use a scale if you want to be precise.
- Don't overmix. Once the flour goes in, mix just until combined. More mixing does not improve brownies.
- Line the pan. Parchment paper with an overhang makes removing and slicing the brownies much easier. It's worth the extra step.
- Check for doneness early. Start checking around the 22-minute mark. You're looking for thick, glossy crumbs-not a clean toothpick.
- Toast the marshmallow topping carefully. A kitchen torch works best. If you use the broiler, watch it closely-it goes from toasted to burned very fast.
FAQs - Hot Chocolate Brownies
- Can I use marshmallow bits instead of fluff? Marshmallow bits or mini marshmallows work great as a topping, but they won't have the same creamy texture as marshmallow fluff.
- How do I store these brownies? Store the brownies in an airtight container at room temperature for up to 3 days. For longer storage, wrap them tightly in plastic wrap and freeze for up to 2 months.
- Can I use regular brownie mix? This homemade recipe yields a fudgy texture that's hard to beat, but you can use brownie mix as a shortcut if needed!

Storing and Freezing Instructions
Store leftover brownies in an airtight container at room temperature for up to 2-3 days. If you prefer them chilled, they'll keep in the refrigerator for up to a week-just know the texture will be slightly firmer when cold. For longer storage, wrap individual brownies tightly in plastic wrap and place them in a freezer-safe bag. Freeze for up to 2 months, then thaw at room temperature before serving. They hold up well, which is convenient and also a little dangerous.
FOR MORE RECIPES LIKE THIS ONE:
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Recipe

Hot Chocolate Brownies
Ingredients
- ¾ cup unsalted butter
- ¼ cup neutral oil canola or vegetable
- 6 oz dark chocolate 60-70% chopped
- ¼ cup plus 2 tablespoons Dutch-process cocoa powder
- 1 cup plus 2 tablespoons granulated sugar
- ¾ cup packed brown sugar
- 2 large eggs room temperature
- 2 large egg yolk save the whites for the marshmallow fluff
- 1 ½ teaspoon vanilla extract
- 1 teaspoon fine sea salt
- ¾ cup all-purpose flour
- 1 teaspoon cornstarch
For the Marshmallow Fluff
- Note: You can substitute a 7-ounce jar of store-bought marshmallow fluff if desired.
- 2 egg whites room temperature from above
- 1 pinch salt
- 3 tablespoons granulated sugar
- ½ cup light corn syrup
- 2 tablespoons water
- 1 teaspoon vanilla extract
- ¼ cup melted dark chocolate cooled
For the ganache
- ½ cup heavy whipping cream
- ¾ cups semi sweet chocolate
Instructions
For the brownies
- Preheat the oven to 350°F (175°C). Line an 8×8-inch metal baking pan with parchment paper, leaving overhang on two sides for easy removal. Lightly spray the parchment with nonstick spray and set the pan aside.
- In a medium saucepan over low heat, combine the butter, oil, and chopped dark chocolate. Stir constantly until the mixture is mostly melted, then remove the pan from the heat and continue stirring until completely smooth. Whisk in the cocoa powder until glossy and fully incorporated. Allow the mixture to cool to about 120°F; it should feel warm to the touch but not hot, with no visible steam.¾ cup unsalted butter, ¼ cup neutral oil canola or vegetable, 6 oz dark chocolate 60-70%, ¼ cup plus 2 tablespoons Dutch-process cocoa powder
- In a large mixing bowl, combine the granulated sugar, brown sugar, eggs, and egg yolk. Beat with a hand mixer or whisk on medium to medium-high speed for 3-4 minutes, until the mixture is pale, thick, and glossy and falls in ribbons when lifted. Whisk the vanilla extract and salt into the egg mixture. With the mixer on low speed, slowly pour in the warm chocolate mixture and mix just until fully combined and smooth, being careful not to overmix.1 cup plus 2 tablespoons granulated sugar, ¾ cup packed brown sugar, 2 large eggs room temperature, 2 large egg yolk, 1 ½ teaspoon vanilla extract, 1 teaspoon fine sea salt
- Add the flour and cornstarch to the bowl. Gently fold the dry ingredients into the batter using a spatula until just combined, stopping as soon as no dry flour remains to keep the brownies dense and fudgy.¾ cup all-purpose flour, 1 teaspoon cornstarch
- Pour the batter into the prepared pan and smooth the top evenly. Bake for 22-26 minutes, until the edges are set and the center is still slightly soft. A toothpick inserted into the center should come out with thick, glossy crumbs rather than clean.
- Remove the brownies from the oven and place the pan on a wire rack. Let the brownies cool completely in the pan for at least 1 hour before slicing, as they will continue to set as they cool.
For the Marshmallow Fluff
- In the bowl of a stand mixer fitted with the whisk attachment, whisk the egg whites and salt on medium-high speed until frothy, about 3 minutes. Reduce speed to the lowest setting to maintain stability. 2 egg whites,1 pinch salt2 egg whites room temperature, 1 pinch salt
- In a small saucepan, combine the sugar, corn syrup, water, and vanilla over medium heat. Heat until the sugar is fully dissolved and the mixture is about 235Fabout 3-5 minutes.3 tablespoons granulated sugar, ½ cup light corn syrup, 2 tablespoons water, 1 teaspoon vanilla extract
- Turn the mixer back to medium-high speed and slowly pour the hot sugar syrup down the inside rim of the mixing bowl, letting it trickle down the sides to avoid scrambling the egg whites. This process should take about 2 minutes.
- Once all the sugar syrup is incorporated, increase the mixer speed to high and whip for 5 minutes, or until the mixture becomes stiff and shiny.
- While the marshmallow fluff is mixing, melt the dark chocolate in the microwave in 15-20 second intervals, stirring until smooth. Let cool slightly.¼ cup melted dark chocolate cooled
- Using a rubber spatula, gently fold the melted chocolate into the marshmallow fluff. Only fold 3-4 times to create a beautiful streaked effect.
FOR THE GANACHE
- Place the cream in a medium microwave-safe bowl and heat until hot and slightly bubbly, ensuring it doesn't boil over. Start with 30-second intervals, checking until bubbly.½ cup heavy whipping cream
- Remove from the microwave and add the chocolate. Let the mixture sit for 5 minutes without stirring. If the chocolate hasn't fully melted after 5 minutes, microwave again in short intervals until smooth.¾ cups semi sweet chocolate
- Once ready, stir until everything melts and the mixture is smooth. Pour the ganache over the cooled brownies and spread evenly.
- Spread the marshmallow fluff evenly over the top. For an extra touch, toast the marshmallow topping with a kitchen torch, if desired.

Jamie Murphy says
These brownies were amazing! I've never made my own marshmallow fluff and it turned out perfectly!
Jamie Murphy says
These brownies were amazing! I'll be making them again. I've never made my own marshmallow fluff and it turned out perfectly!
Anonymous says
This worked exactly as written, thanks!