For the Swiss meringue buttercream: In the bowl of an electric mixer fitted with the whisk attachment, thoroughly whisk together the sugar and egg whites. Set the bowl over a pan of boiling water. Whisking constantly, heat to 145 to 150 degrees F. Return the mixing bowl to the stand and whisk until stiff and the bottom of the bowl comes to room temperature, about 8 minutes.
Change to the paddle attachment and turn the mixer to low speed. Add the butter, a few cubes at a time, until incorporated. Mix at medium speed until light and fluffy. Add the vanilla and mix until combined. Use 4 cups for the flavored buttercreams in this recipe, and reserve the remaining 4 cups for another use.
For the chocolate mascarpone buttercream: Fold the melted and cooled chocolate and the mascarpone cheese into 2 cups of the Swiss meringue buttercream.
For the Zinfandel buttercream: Blend the Zinfandel wine into 2 cups of the Swiss meringue buttercream. Spoon the mixture into a pastry bag fitted with a large straight pastry tip.
For the cupcakes: Preheat the oven to 325 degrees F. Line standard cupcake pans with 27 cupcake liners.
In the bowl of an electric mixer fitted with the paddle attachment, combine the sugar, buttermilk, and oil. Mix well. Add the eggs and vanilla, mixing on low speed until completely mixed together. Sift the flour, cocoa powder, baking soda, and sea salt into a separate bowl and whisk together. In a liquid measuring cup, mix the water with the instant coffee, dissolving the coffee powder completely. Add 1/2 the dry ingredients to the buttermilk mixture just until incorporated. Mix in the water and coffee mixture. Add the rest of the dry ingredients, mixing until combined, and then beat for 2 minutes.
Fill the cupcake liners 3/4 full and bake until golden brown, 17 to 20 minutes. Cool the cupcakes completely.
For the chocolate frosting: Heat the cream until hot but do not boil. Remove from the heat and add the chocolate. Stir until completely melted and smooth. Set aside to cool. In the bowl of an electric mixer fitted with the paddle attachment, beat the butter and salt until smooth. Add 1/2 the powdered sugar, mixing until smooth. Add the chocolate and the remaining powdered sugar and mix until creamy. Adjust to desired spreading consistency with additional cream or powdered sugar, if needed. Place in a pastry bag fitted with a large star tip.
To assemble: Remove a piece from the center of each cupcake and fill the cupcake with about 1 tablespoon chocolate mascarpone Swiss buttercream. Pipe a generous amount of chocolate frosting onto the top of the cupcake. Pipe a dollop of Zinfandel Swiss meringue buttercream on top of the chocolate frosting. Top with half a strawberry and drizzle with melted chocolate.
If using unbleached all-purpose flour instead of unbleached pastry flour, reduce the flour quantity to 2 cups.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.