Name: Decadent Black Cocoa Cake with Silky Mascarpone Frosting
Prep time: 25 min
Cook time: 35 min
Total time: 2 h
Cuisine: American
Ingredients: 1 3/4 cups (220 g) all-purpose flour; 3/4 cup (65 g) black cocoa powder; 1 1/2 cups (300 g) granulated sugar; 1/2 cup (100 g) light brown sugar; 1 tsp baking soda; 1/2 tsp baking powder; 1/2 tsp salt; 1/2 cup (120 ml) vegetable oil; 1/4 cup (60 g) unsalted butter, melted; 3 large eggs, room temperature; 1 cup (240 ml) buttermilk, room temperature; 1 tsp vanilla extract; 1 1/2 cups (360 ml) heavy cream, chilled (for frosting); 1 cup (250 g) mascarpone cheese, chilled; 1/2 cup (60 g) powdered sugar; Pinch of salt (for frosting)

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This Decadent Black Cocoa Cake with Silky Mascarpone Frosting is for anyone who wants an intensely chocolatey, elegantly smooth cake without fuss. I’ve made versions of this cake for birthdays and small dinner parties; the black cocoa gives a striking color and the mascarpone keeps the frosting lush and never cloying. The recipe is forgiving and yields a bakery-quality result at home.

Why Make This Recipe

Deep, dramatic chocolate flavor from black cocoa that tastes richer than standard cocoa.
Silky mascarpone frosting is less sweet than buttercream and stays stable at room temperature for a few hours.
Works well for celebrations — looks impressive but is straightforward to bake.
Good make-ahead candidate: layers can be baked and frozen in advance.
Personal insight: I love this because the mascarpone balances the bitter-sweet cake so each bite feels elegant, not heavy.

Also, if you enjoy the dramatic look of a dark crumb you might like this take on a black velvet cake.

Recipe Overview

Prep time: 25 minutes (plus chilling time for frosting)
Cook time: 30–35 minutes per 8-inch pan
Total time: about 1 hour plus cooling and frosting (allow 2–3 hours total)
Servings: 10–12 slices (two 8-inch layers)
Difficulty: Medium — straightforward batter but attention to temperature and aeration helps
Method: Creaming/oil-based chocolate cake baked in two round pans, cooled, then filled and frosted with whipped mascarpone.

My Experience Making This Recipe

I tested this cake several times, adjusting cocoa ratios and frosting sweetness to get balance. Early attempts had a slightly gummy crumb; I solved that by sifting dry ingredients and using a mix of oil and a little butter for tenderness and structure.

How to Make Decadent Black Cocoa Cake with Silky Mascarpone Frosting

You’ll make a single batter, divide it between two 8-inch pans, and bake at 350°F (175°C) until a skewer comes out with just a few moist crumbs (about 30–35 minutes). Let the layers cool completely in the pans for 10 minutes, then transfer to a rack to finish cooling. For the frosting, whip cold mascarpone with chilled heavy cream, powdered sugar, and a pinch of salt until it holds soft peaks; spread between and around layers. Chill briefly so the frosting firms before slicing.

Expert Tips for Success

Weigh dry ingredients when possible; 1 3/4 cups (220 g) flour is more accurate by weight.
Sift black cocoa and flour together to break up lumps and ensure an even, velvety crumb.
Use room-temperature eggs but cold mascarpone and cold heavy cream for the frosting to whip up light and stable.
An instant-read thermometer is handy: cakes are done around 200–205°F (93–96°C) internal.
Chill the cake for 20–30 minutes after crumb-coating to make final frosting smooth and easier to handle.

How to Serve Decadent Black Cocoa Cake with Silky Mascarpone Frosting

Serve slightly chilled or at cool room temperature (50–68°F / 10–20°C) so the frosting keeps texture.
Add fresh raspberries or cherries for brightness and a color contrast.
Dust the top with a little black cocoa or cocoa nibs for texture and visual interest.
Bring it to special occasions like anniversaries or dinner parties — it pairs well with espresso or a fortified wine.

Storage and Reheating Guide

Store unfrosted layers wrapped tightly in plastic wrap at room temperature for up to 24 hours or in the refrigerator for up to 3 days. Frosted cake keeps in an airtight container in the refrigerator for 3–4 days. For longer storage, freeze individual layers (wrapped in plastic and foil) for up to 3 months; thaw in the fridge overnight before frosting or assembling. To serve, let chilled cake sit at room temperature for 20–30 minutes to soften the frosting slightly; do not microwave frosted slices (that will ruin texture).

Recipe Variations

Gluten-free: Substitute a 1:1 gluten-free flour blend (measure by weight) and add 1/2 teaspoon xanthan gum if your blend lacks it.
Dairy-free/vegan: Use a plant-based mascarpone alternative or chilled coconut cream whipped with a little dairy-free cream cheese; replace eggs with flax eggs and use neutral oil.
Raspberry or cherry filling: Spoon a thin layer of warmed raspberry preserves (strained) between layers for tart contrast.
Extra-moist: Fold 2 tablespoons espresso or strong coffee into the batter to enhance chocolate notes without adding coffee flavor.

Nutritional Highlights

This cake is rich and calorie-dense; serve smaller slices (about 1/10–1/12 of cake) to manage portions.
Key allergens: contains gluten, dairy, and eggs. Substitute carefully for allergy needs.
The mascarpone frosting is higher in fat but lower in added sugar than many buttercreams, which some home bakers prefer for balance.

Troubleshooting Common Issues

Dry crumb: Don’t overbake; check at 30 minutes and use an instant-read thermometer (200–205°F). Also don’t overmix the batter once you add flour.
Soggy center: If layers are underbaked in the middle, bake a few minutes longer and rotate pans; make sure oven temperature is accurate with a thermometer.
Runny frosting: Ensure mascarpone and cream are very cold before whipping and avoid overwhipping mascarpone alone (it can break and become grainy).

Frequently Asked Questions

Q1: Can I use regular cocoa instead of black cocoa?
A1: Yes, but black cocoa produces an almost-black crumb and a drier, more intense flavor. If using regular Dutch-processed cocoa, you may lose some depth and color; reduce any added liquid by a tablespoon if batter seems loose.

Q2: How do I prevent the mascarpone frosting from becoming grainy?
A2: Keep mascarpone and cream chilled, whip cream to soft peaks first, then gently fold in whipped mascarpone or whip both together at low speed. Avoid high-speed overbeating, which can cause separation.

Q3: Can I bake this as a single-layer sheet cake?
A3: Yes — bake in a 9×13-inch pan at 350°F (175°C) for 25–30 minutes, checking doneness with a skewer and adjusting time as needed.

Q4: How far ahead can I assemble the cake?
A4: You can bake layers and freeze them for up to 3 months. Assemble and frost up to 24 hours before serving for best texture; keep refrigerated and allow 20–30 minutes at room temperature before serving.

Conclusion

For more inspiration on pairing mascarpone with fruit and layers, check this Black Forest–inspired layer cake. If you like a fruit-forward contrast, this Chocolate Raspberry Cake shows a bright pairing that works well with mascarpone. Want different mascarpone frosting techniques? Read this Silky Chocolate Mascarpone Frosting guide for whipping tips. For a whipped mascarpone approach with chocolate, see this Chocolate Mascarpone Whipped Cream example. If you enjoy testing highly rated chocolate cakes, Yotam Ottolenghi’s take offers interesting technique notes: World’s Best Chocolate Cake.

Enjoy baking — and if you try it, tell me how you adjusted the frosting or fillings so I can share tips for your next bake.

Decadent Black Cocoa Cake with Silky Mascarpone Frosting