For the cake:
- 1 1/2 cups egg whites (from about 1 dozen eggs), at room temperature
- 1 1/4 teaspoons cream of tartar
- 1/2 teaspoon salt
- 1 1/2 cups sugar
- 1 1/8 cups sifted cake flour
- 1 teaspoon pure vanilla extract
For the berries:
- 1/2 pint raspberries
- 1/2 pint blackberries or blueberries
- 1 pint strawberries, hulled (green tops removed) and sliced
- 1/4 cup orange liqueur
- 1 teaspoon fresh lemon juice
- 2 mint leaves, julienned
- Powdered sugar, for garnish
Preheat the oven to 375 degrees F.
In a mixer fitted with a whisk attachment, whip the egg whites until foamy. Add the cream of tartar and salt and continue whipping until soft peaks form. With the mixer running, gradually add 1 cup of the sugar and continue whipping until stiff and the sugar has dissolved, about 30 seconds. Sift the remaining 1/2 cup sugar with the presifted cake flour 3 times, to aerate the mixture. Fold into the egg whites, then fold in the vanilla.
Spoon the batter into ungreased extra-large muffin tins. Bake until light golden brown, 20 to 25 minutes. Cool the cakes by turning the muffin tin upside down and suspending it with small ramekins placed in the corners until they cool to room temperature. Run a butter knife around the cakes to loosen, then knock the cakes out onto a plate, or work them out with your fingers. The outside of the cake will remain in the pan leaving the cake whiter and more angelic looking.
Make the macerated fruit by lightly toss together the fruit, liqueur, lemon juice, and mint and let macerate in the refrigerator for at least 30 minutes before serving. Hollow out the center of the large cup cakes. Fill the cavity with some fruit then turn them over onto dessert plates. Spoon the macerated berries and juices over the cakes and sprinkle with powdered sugar