Here’s a cozy, indulgent dessert I love: a hot cocoa-inspired cake bright with flavor and topped with dreamy marshmallow buttercream.

Why You’ll Love This Recipe

I love this cake because it captures the feeling of curling up with a mug of hot chocolate on a chilly day — but in cake form. The cake itself is rich and chocolatey thanks to the cocoa powder and hot cocoa mix, while the marshmallow buttercream frosting brings in that gooey fluffiness I crave this time of year. It’s comforting, festive, and just a bit nostalgic.

Ingredients

(Note: All ingredient amounts are listed in the recipe card below.)
For the Hot Cocoa Cake:
1 cup canola oil, plus more for baking pan
2 ¼ cups all-purpose flour, spooned and leveled, plus more for baking pan
¼ cup unsweetened cocoa powder
3 (1.38-oz) envelopes hot cocoa mix
1 ¼ cups granulated sugar
1 tsp baking powder
½ tsp baking soda
½ tsp kosher salt
2 large eggs
1 tsp pure vanilla extract
1 ¼ cups whole milk

For the Marshmallow Buttercream:
1 cup (2 sticks) unsalted butter, at room temperature
2 cups confectioners’ sugar
1 tsp pure vanilla extract
¼ cup heavy cream
¼ tsp kosher salt
2 (7-oz) containers Jet-Puffed Marshmallow Creme

Directions

Preheat the oven to 350 °F (≈177 °C). Grease and flour your cake pan (I use a 9″ round or 8″ square) with a bit of canola oil and then dust with flour.
In a large mixing bowl, combine the flour, cocoa powder, hot cocoa mix (all three envelopes), sugar, baking powder, baking soda, and kosher salt. Mix until evenly distributed.
Add the canola oil, eggs, vanilla extract, and whole milk to the dry ingredients. Stir until everything is just combined and smooth; be careful not to over-mix.
Pour the batter into the prepared pan, spreading it evenly.
Bake in the preheated oven until a toothpick inserted into the center comes out clean or with a few moist crumbs (about 30-35 minutes, but check early if your pan is smaller or thinner). Let the cake cool in the pan for about 10 minutes, then turn out onto a wire rack and cool completely before frosting.
While the cake is cooling, prepare the marshmallow buttercream: In a large bowl (or stand mixer), beat the room-temperature unsalted butter until creamy and light in color (about 2-3 minutes). Gradually add the confectioners’ sugar, vanilla extract, heavy cream, and kosher salt. Beat until smooth and slightly fluffy. Then beat in the marshmallow creme (both containers) until the frosting is smooth, fluffy, and well-incorporated. (Recipes show that this style of marshmallow buttercream results in a light, cloud-like frosting. (Our Best Bites))
Once the cake is completely cooled, spread the marshmallow buttercream evenly over the top (and sides if you like). You can make it simple or pipe decorative swirls.
Optional: For extra “hot cocoa” effect, top with mini-marshmallows, a dusting of cocoa powder, or even chocolate shavings.
Slice and serve.

Servings and Timing

This cake yields about 8-10 servings (depending on how large the slices are).

Prep time: ~20 minutes
Bake time: ~30-35 minutes
Cooling + frosting: ~15-20 minutes
Total time: ~65-75 minutes

Variations

Swap the canola oil for melted coconut oil or light olive oil for a slightly different flavor.
Use half whole milk / half buttermilk for a slightly tangier cake and extra moist crumb.
Add a teaspoon of instant coffee granules to the batter to deepen the chocolate “hot cocoa” flavor.
Infuse the buttercream with a hint of peppermint extract or orange zest for a seasonal twist.
Instead of a single layer, divide the batter into two smaller pans for a layered cake and spread frosting between layers.
For a gluten-free version, use a 1:1 gluten-free baking flour in place of the all-purpose flour .

Storage/Reheating

Store leftovers in an airtight container at room temperature for up to 2 days, or in the refrigerator for up to 4 days. If refrigerated, bring to room temperature before serving so the buttercream isn’t too firm. The cake isn’t really meant for reheating, but you can warm a slice in the microwave for ~10-15 seconds to get that “just baked, warm hot cocoa” feel.

FAQs

How do I know the cake is done baking?

I insert a toothpick into the center; if it comes out clean or with a few moist crumbs (but not raw batter) it’s done. If the cake still jiggles a lot in the center, give it a few more minutes.

Can I use low-fat milk instead of whole milk?

You could, but I prefer whole milk here for richness and moisture. If you use low-fat, the cake may be slightly less tender.

What does the hot cocoa mix add to the cake?

The hot cocoa mix adds flavor reminiscent of drinking hot chocolate – a sweet cocoa taste plus a bit of that mix sweetness – boosting the cocoa powder base. Versions of hot cocoa cakes use this trick to intensify the “hot cocoa in dessert” feeling.

Is the marshmallow buttercream very sweet?

Yes, it is definitely sweet and rich — the marshmallow creme adds extra sugary gooeyness on top of the butter and sugar base. I like it for special occasions or when I’m in the mood for indulgence.

Can I make the cake ahead of time?

Yes. You can bake the cake layer(s) ahead, wrap them tightly in plastic wrap once cooled, and refrigerate for up to a day or freeze for up to a month. Freeze in a sealed bag with minimal exposure. Then thaw, frost, and serve when ready.

How do I store the frosted cake?

Once frosted, store the cake covered (cake dome or airtight container) in the refrigerator if your room is warm. Bring to room temperature about 30 minutes before serving for best texture (so the buttercream softens).

Can I skip the marshmallow creme and just use regular buttercream?

Yes — you can simplify by making a classic buttercream (butter + confectioners’ sugar + vanilla + cream) if you prefer something less sweet or less marshmallow-forward. The cake will still be delicious.

Can I make this into cupcakes instead of a full cake?

Absolutely. Divide the batter into cupcake liners and bake at ~350 °F for about 18-22 minutes (or until a toothpick comes out clean). Frost with the marshmallow buttercream once cooled.

Can I freeze leftover slices?

Yes. Freeze individual slices wrapped tightly in plastic wrap and then foil, for up to 2 months. Thaw in refrigerator overnight and let come to room temperature before serving.

Conclusion

I find this Sweater Weather Hot Cocoa Cake to be one of my favorite ways to bring cozy warmth into dessert form. With its hot cocoa-flavored cake and fluffy marshmallow buttercream, it’s perfect for chilly nights, gatherings, or when I simply want to treat myself. Whether you make it for a special occasion or just because, I hope it brings that comforting “cup of hot chocolate” feeling to your table.