Sabayon cakes. This batter in this cake magically separates into a luscious, pudding-like sabayon layered on the bottom and light as air grapefruit cake on top.
- 1 tablespoon unsalted butter, at room temperature
- 3 large eggs
- ½ cup granulated sugar
- 2 tablespoon all-purpose flour
- 2 teaspoon red grapefruit zest
- ¼ cup freshly squeezed red grapefruit juice
- 1 cup whole milk
- 1 pinch kosher salt
- 2 tablespoon confectioners sugar
- 3 cup boiling water, or more as needed
Place the oven rack in the center position and preheat to 350 degrees. Butter the interiors of six 6‑ounce ramekins and place in a baking dish or roasting pan.
In a large bowl, whisk egg yolks and sugar together until light; whisk in the flour. Followed by the grapefruit juice, then the milk and zest. In a separate bowl use an electric mixer to beat egg whites and salt until soft peaks form. Add to grapefruit batter and fold in gently with a whisk..
Divide batter among prepared ramekins; place baking dish in oven and fill with boiling water to reach halfway up sides of ramekins. Bake until puffed and lightly browned (but the grapefruit sabayon is still visible in bottom), 20 to 25 minutes. Serve warm, dusted with confectioners’ sugar.