Cream butter and sugar. Beat in the egg yolks.
Sift together 3 times the flour, salt and baking powder.
Add flour alternately with the milk to the creamed mixture, beating after each addition. Add the vanilla. Beat egg whites stiff and fold in.
Drain the cherries. Place them in a buttered spring-form cake pan. Pour the batter over them. Swish the batter with a fork to distribute cherries through the cake.
Bake 35 to 40 minutes in a preheated 375° oven.