5-6 ripe (but not too ripe) aprocots (or dark plums) sliced
1/4 cup unsalted butter (1/2 stick)
1/2 cup packed light or dark brown sugar
Preheat the oven to 350º.
Melt 1/2 stick of butter in a 11" round (or 9x13) pan. Spread the melted butter evenly over the bottom of the pan, as well as up the sides, with a pastry brush or paper towel (let the pan cool a little so you don't burn yourself). Add the brown sugar to the melted butter by sprinkling and pressing it evenly over the bottom of the pan.
[Alternatively: If, like me, you have only one of those pans with a push-up bottom, melt the butter separately in a small pan, add the sugar to make a thick sludge, then spread that sludge into the cake pan.]
Place the sliced apricots (or plums) in a single layer over the brown sugar in a nice pattern. Set aside while you make the cake.
1/2 cup unsalted sweet cream butter (1 stick), room temperature
1 1/2 cup sugar
4 eggs, separated
1 cup sour cream
1 tsp. pure vanilla
1 3/4 cup all-purpose flour, sifted
1/2 teaspoon baking powder
1/4 teaspoon baking soda
Cream the butter and sugar until light. Add egg yolks, sour cream and vanilla and beat until fluffy.
Sift together flour, baking powder and baking soda and add to the sour cream mixture. Mix until incorporated.
In a separate bowl, beat the egg whites until they form stiff peaks. Gently fold into the cake batter. Pour into the prepared pan over the apricot topping. Spread the batter evenly.
Bake at 350º for 30-35 minutes, or until a toothpick inserted in the middle comes out clean. When the cake has cooled a little, run a knife around the edges to loosen it and invert it on a serving platter. Wait about 30 seconds before lifting the pan off to ensure that the apricot-brown sugar glaze remains intact.
Serve warm or at room temperature, with or without vanilla ice cream or a dollop of whipped cream. Cake is moist enough to keep for 2-3 days.
Source: Food52 (via Maggie)