Tool

• Electric hand mixer or stand mixer

• Mixing bowls

• Small saucepan

• Piping tips

Ingredients

For the Cake

• ½ cup whole milk, room temp

• ½ cup sour cream, room temp

• 5 large egg whites, room temp

• 2 tsp vanilla extract

• 3 cups unbleached cake flour

• 2 cups granulated sugar

• 2 tsp baking powder

• ¾ tsp salt

• 1 cup unsalted butter, very soft

For the Filling

• 5 large egg yolks

• ½ cup granulated sugar

• 1 tsp cornstarch

• ¾ cup whole milk

• 1 tbsp coffee liqueur

• 16 oz mascarpone, room temp

Swiss Meringue Buttercream

• 5 large egg whites, room temp

• 1½ cups granulated sugar

• Pinch of sea salt

• 2 cups unsalted butter, softened

• 1 tsp vanilla extract

• 3 tbsp coffee liqueur

For Assembly

• ¾ cup hot water

• 1½ tsp espresso powder

• 3 tbsp coffee liqueur

• ¼ cup unsweetened cocoa powder

• 12 chocolate‑covered espresso beans (optional)

Direction

Cake

1. Heat the oven to 350ºF. Prepare two 8‑inch round pans by greasing them and lining the bottoms with parchment. If you have baking strips, wrap the pans to help the layers bake evenly.

2. In a medium bowl, whisk together the milk, sour cream, egg whites, and vanilla. Set aside.

3. Add the flour, sugar, baking powder, and salt to the bowl of a stand mixer fitted with the paddle. With the mixer on low, add the soft butter a tablespoon at a time until the mixture becomes sandy and crumbly.

4. Slowly pour in half of the milk mixture while the mixer runs on low. Mix just until combined, then scrape down the bowl. Add the remaining liquid and beat on medium until the batter becomes light and slightly fluffy.

5. Divide the batter between the pans and bake for about 35 minutes, or until a toothpick comes out clean. Cool the cakes in the pans for 15 minutes, then turn them out onto a rack, remove the parchment, and let them cool completely.

Mascarpone Filling

1. Warm the milk in a small saucepan over medium heat until it begins to steam and tiny bubbles form at the edges.

2. In a separate bowl, whisk the egg yolks, sugar, and cornstarch until smooth.

3. Slowly pour the hot milk into the yolk mixture while whisking. Return everything to the saucepan and cook over medium‑low, whisking constantly, until the custard thickens and holds a trail from the whisk. It should reach roughly 200ºF.

4. Remove from heat and stir in the coffee liqueur. Transfer to a clean bowl, press plastic wrap directly onto the surface, and chill until it reaches room temperature. (To cool quickly, place the bowl in an ice bath and stir for a few minutes.)

5. In another bowl, gently loosen the mascarpone with a whisk. Fold in the cooled custard in two additions, mixing just until smooth. Chill until assembly.

Swiss Meringue Buttercream

1. Combine the egg whites, sugar, and salt in a heatproof bowl that fits over a pot of simmering water. Whisk briefly, then set the bowl over the steam.

2. Heat the mixture, stirring constantly, until it reaches 160ºF.

3. Transfer to a stand mixer fitted with the whisk and beat on medium until the meringue becomes thick, glossy, and cool to the touch — about 10–12 minutes.

4. Reduce speed to medium‑low and add the softened butter one tablespoon at a time, letting each piece fully blend in.

5. Add the vanilla and coffee liqueur, then whip on medium‑high until the buttercream is fluffy and stable. (If it seems loose, chill briefly and re‑whip.)

6. Portion ¾ cup of buttercream into a piping bag fitted with a closed star tip, and 1 cup into a bag fitted with a round tip. Cover the remaining frosting.

Assembly

1. Stir together the hot water, espresso powder, and coffee liqueur to make the soaking syrup. Let it cool slightly.

2. Slice each cake layer horizontally to create four thin layers. Transfer the mascarpone filling to a piping bag.

3. Place the first layer on a cake stand, cut side up. Brush with about 5 tablespoons of the coffee syrup.

4. Spread a thin coat of buttercream over the surface. Pipe a round‑tip border around the edge to contain the filling. Add about 1 cup of mascarpone filling and smooth it out. Dust lightly with cocoa powder.

5. Repeat the layering process two more times. For the final layer, place it bottom side up for a flat top.

6. Frost the entire cake with the remaining buttercream. You can leave the sides thick or scrape them for a semi‑naked look.

7. Dust the top with cocoa powder, then clear a ring around the edge for piping. Add decorative buttercream dollops and finish with chocolate‑covered espresso beans if you like.

8. Chill the cake for at least 1 hour before slicing.

Nutrition -

(Per Serving)

Calories: 1064 kcal Carbohydrates: 99 g Protein: 12 g Fat: 69 g Saturated Fat: 42 g Polyunsaturated Fat: 2 g Monounsaturated Fat: 14 g Trans Fat: 2 g Cholesterol: 250 mg Sodium: 308 mg Potassium: 184 mg Fiber: 2 g Sugar: 73 g Vitamin A: 2157 IU Vitamin C: 0.1 mg Calcium: