Preheat oven to 350°F.

Sift together in a large mixing bowl:

2 1/2 cup sifted all-purpose flour
1 2/3 cups sugar
4 tsp. baking powder
1/2 tsp. salt

Add:

1/2 cup (1 stick) butter
1 1/2 cups milk
1 1/2 tsp. vanilla

Beat well for 2 minutes.

Add:

5 unbeaten egg yolks

Beat 2 more minutes.

Pour into greased pans with wax paper on bottom.

Makes 2 layers or 1 (9 x 13-inch) oblong (loaf) cake.

Bake layers for 30 to 35 minutes, oblong cake for 40 to 45 minutes, or until a wooden pick inserted in center comes out clean.