Beat egg yolks, gradually adding sugar. Sift dry ingredients together, add to egg mixture. Stir in 1/4 of beaten egg whites, and pecans, then fold in remaining whites. Line 2 layer cake pans with wax paper, butter and flour them. Fill and bake at 350 degrees for 30 minutes. Cool upside down on racks. Frost layers with whipped cream. Sprinkle with ground pecans.