Explanations vary as to the meaning behind this dessert’s name, which translates as “English soup.” Some say it refers to its similarity to the English dessert called a trifle. Others believe it is a corruption of the verb inzuppare, “to sop.” One of the key ingredients, alchermes, is a bright red liqueur that gets its color from kermes, an insect-based dye. Because alchermes may be hard to find, another red liqueur, such as Chambord, can be substituted.
For the sponge cake:
- Butter for greasing pan
- 1/3 cup cake flour, plus more for dusting
- 4 eggs, separated
- 1/3 cup granulated sugar
- Pinch of salt
- 1 tsp. baking powder
For the custard:
- 2 cups milk
- 1 large lemon zest strip
- 1 whole egg, plus 3 egg yolks
- 1/3 cup granulated sugar
- 1/4 cup all-purpose flour
- 1 tsp. sambuca
- 1/4 cup rum, or more to taste (optional)
- 1/4 cup alchermes (see note above), Chambord or framboise
- 1/2 cup heavy cream
- 2 tsp. confectioners’ sugar
- About 2 Tbs. grated bittersweet chocolate for sprinkling
Preheat an oven to 375°F. Butter an 8-inch round cake pan, dust with flour and tap out the excess.
To make the sponge cake, in a bowl, using an electric mixer on medium speed, beat together the egg yolks and granulated sugar until thick and pale yellow, about 5 minutes. In a separate bowl, using the mixer with clean beaters, beat the egg whites on medium speed until frothy. Add the salt and beat on medium-high speed until stiff, glossy peaks form. In a small bowl, whisk together the 1/3 cup flour and the baking powder. Using a rubber spatula, gradually fold the flour mixture into the yolk mixture. Stir about one-third of the whites into the yolk mixture, and then gently fold in the remaining whites just until no white streaks remain.
Pour the batter into the prepared pan. Bake until a toothpick inserted into the center comes out clean, about 30 minutes. Transfer the pan to a wire rack, let cool for about 10 minutes, and then turn the cake out onto the rack.
While the cake is baking, make the custard: In a saucepan over medium heat, combine the milk and lemon zest strip and heat until small bubbles appear around the edges of the pan. Remove from the heat, let cool slightly, and then remove and discard the lemon zest. Meanwhile, in a bowl, whisk together the whole egg, egg yolks and granulated sugar until well blended. Whisk in the flour 1 Tbs. at a time, and then continue whisking until the mixture is thick and pale yellow, about 5 minutes. Slowly pour the hot milk into the egg mixture while stirring constantly. Then pour the contents of the bowl into the saucepan, place over low heat and heat gently, stirring constantly, until the mixture is thick enough to coat the back of a spoon, about 7 minutes. Remove from the heat and pour through a fine-mesh sieve into a bowl. Stir in the sambuca. Let cool to room temperature, stirring from time to time to prevent a skin from forming.
To assemble, using a serrated knife, cut the cake into slices about 2 by 3 inches and 1/4 inch thick. Line the bottom of glass serving bowls with some of the cake slices. Sprinkle the cake slices with some of the rum and some of the alchermes. Spread half of the custard over the cake slices. Top with another layer of cake slices, sprinkle with the rum and alchermes, and spread the remaining custard over the top. Repeat to make a final layer of cake, rum and alchermes. Cover and refrigerate for several hours, or preferably overnight, before serving.
In a bowl, combine the cream and confectioners’ sugar, and beat with a balloon whisk until medium-stiff peaks form. Spoon an equal amount of the cream on top of each bowl and sprinkle with the grated chocolate. Serve immediately. Serves 6.
Adapted from Williams-Sonoma Essentials of Italian by Michele Scicolone (Oxmoor House, 2007).