This Hot Chocolate Layer Cake brings all the comfort of a warm mug of cocoa into a rich, layered dessert. I get incredibly moist chocolate cake, soft marshmallow fluff buttercream, and a glossy homemade chocolate fudge sauce in every bite. It feels indulgent, wintery, and perfect for celebrations or cozy evenings at home.
Why You’ll Love This Recipe
I love that this cake captures true hot-chocolate flavor. The cake layers stay moist thanks to sour cream and oil, the marshmallow buttercream tastes exactly like melted marshmallows, and the fudge sauce adds a gooey richness that ties everything together. Even though it looks like a showstopper, the steps are simple and approachable.
Ingredients
(Tip: You’ll find the full list of Ingredients and measurements in the recipe card below.)
Chocolate Cake
360 g warm coffee or water
360 g all-purpose flour
2 tablespoon cornstarch
300 g granulated sugar
150 g dark brown sugar
75 g unsweetened Dutch cocoa powder
1 ½ teaspoon baking powder
1 ½ teaspoon baking soda
1 ½ teaspoon salt
165 g vegetable oil
270 g sour cream (14–18%), room temperature
3 large eggs, room temperature
3 teaspoon vanilla extract
Chocolate Fudge Sauce
50 g granulated sugar
25 g honey
60 g whole milk
100 g semi-sweet chocolate
10 g unsweetened Dutch cocoa powder
15 g unsalted butter
1 teaspoon vanilla extract
Small pinch of salt
Marshmallow Fluff Buttercream
400 g unsalted butter
225 g powdered sugar
200 g marshmallow fluff
½ teaspoon vanilla paste
Small pinch of salt
Directions
Make The Chocolate Cake
I preheat the oven to 170°C (340°F) and line three 20 cm (8-inch) pans. I whisk all dry ingredients together in one bowl, then mix coffee (or water), oil, sour cream, eggs, and vanilla in another. I pour the wet ingredients into the dry and stir until smooth. I divide the batter between the pans and bake for 28–30 minutes, then let the layers cool completely.
Make The Chocolate Fudge Sauce
I heat the sugar, honey, and milk until the sugar dissolves and the mixture begins to bubble. I pour it over the semi-sweet chocolate and cocoa powder, stirring until melted. I mix in the butter, vanilla, and salt, then let it cool to room temperature.
Make The Marshmallow Buttercream
I whip the butter until pale and fluffy, then add the powdered sugar in two additions. When it’s smooth, I beat in the marshmallow fluff, vanilla paste, and salt until the frosting becomes silky.
Assemble The Cake
I level the cooled cake layers and place the first on my serving plate. I spread on marshmallow buttercream and drizzle 1–2 tablespoons of fudge sauce. I repeat with the next layer. After adding the final layer, I apply a crumb coat and chill the cake briefly. Then I add the remaining buttercream and decorate with marshmallows.
Servings And Timing
Servings: 12 slices
Prep time: 1 hour
Bake time: 28–30 minutes
Total time: about 1 hour 28 minutes
Variations
– I replace the coffee with hot water when I want a milder flavor.
– I add ½ teaspoon cinnamon to the dry ingredients for a spiced hot chocolate version.
– I fold mini marshmallows into the buttercream for extra texture.
– I bake it as a two-layer cake using the same recipe for a simpler presentation.
– I drizzle extra fudge sauce over the top for a richer finish.
Storage/Reheating
I store the cake in the refrigerator in an airtight container or well wrapped. Before serving, I let it come to room temperature so the cake softens and the frosting regains its smooth texture. It’s best enjoyed within 2–3 days. Individual slices can also be frozen and thawed in the fridge.
FAQs
How do I know the cake layers are done?
I insert a cake tester or toothpick in the center. If it comes out clean, the cake is ready.
Can I prepare the cake ahead of time?
Yes, I often bake the layers a day early and freeze them. I refrigerate the frosting and fudge sauce, then assemble everything the next day.
What can I use instead of sour cream?
I substitute full-fat Greek yogurt when needed, using the same amount.
Can I make this with only two pans?
Yes. I bake two layers, let the pans cool, reline one of them, and bake the third layer afterward.
Can I omit the coffee?
Yes. I use hot water instead. The chocolate flavor is still rich and delicious.
Conclusion
This Hot Chocolate Layer Cake is one of my favorite ways to bring hot-cocoa comfort into a dessert. The combination of moist cake, marshmallow buttercream, and luxurious fudge sauce creates a decadent treat that’s perfect for winter gatherings or any moment when I want something truly special. It looks impressive, tastes nostalgic, and comes together beautifully every time. Enjoy every slice.
A rich and indulgent dessert that transforms the cozy flavors of hot chocolate into a moist layered cake with marshmallow fluff buttercream and glossy chocolate fudge sauce. Perfect for winter gatherings or special occasions.
Ingredients
Chocolate Cake:
360 g warm coffee or water
360 g all-purpose flour
2 tbsp cornstarch
300 g granulated sugar
150 g dark brown sugar
75 g unsweetened Dutch cocoa powder
1½ tsp baking powder
1½ tsp baking soda
1½ tsp salt
165 g vegetable oil
270 g sour cream (14–18%), room temperature
3 large eggs, room temperature
3 tsp vanilla extract
Chocolate Fudge Sauce:
50 g granulated sugar
25 g honey
60 g whole milk
100 g semi-sweet chocolate
10 g unsweetened Dutch cocoa powder
15 g unsalted butter
1 tsp vanilla extract
Pinch of salt
Marshmallow Fluff Buttercream:
400 g unsalted butter
225 g powdered sugar
200 g marshmallow fluff
½ tsp vanilla paste
Pinch of salt
Instructions
Preheat the oven to 170°C (340°F) and line three 20 cm (8-inch) cake pans.
In one bowl, whisk together flour, cornstarch, sugars, cocoa powder, baking powder, baking soda, and salt. In another bowl, mix coffee or water, oil, sour cream, eggs, and vanilla extract.
Combine wet and dry ingredients and stir until smooth. Divide the batter evenly into the prepared pans and bake for 28–30 minutes. Let the layers cool completely.
To make the fudge sauce, heat sugar, honey, and milk until bubbling. Pour over chocolate and cocoa powder, stir until melted. Add butter, vanilla, and salt. Cool to room temperature.
For the buttercream, beat butter until fluffy. Add powdered sugar in two batches. Mix in marshmallow fluff, vanilla paste, and salt until smooth.
Level the cooled cake layers. Place the first layer on a serving plate, spread with buttercream and drizzle 1–2 tablespoons of fudge sauce. Repeat with the second layer.
Top with the final cake layer. Apply a crumb coat, chill, then frost with remaining buttercream. Decorate with mini marshmallows and extra fudge if desired.
Notes
Substitute coffee with hot water for a milder chocolate flavor.
Add cinnamon to the cake batter for a spiced variation.
Freeze cake layers in advance for easier assembly.
Use full-fat Greek yogurt instead of sour cream if needed.
Keep the cake covered and refrigerated; bring to room temp before serving.
