3 egg yolks
3 tbsp. sugar
1/2 c. reg. all-purpose flour (sift before measuring)
2 tbsp. cornstarch
2 tsp. baking powder
1/4 tsp. salt
1/2 c. milk
1/2 c. sour cream (or yogurt)
3 egg whites

Cream yolks and sugar. Sift flour again with cornstarch, baking powder and salt. Combine with egg mixture, milk and sour cream. Beat egg whites until stiff, fold in.