* Peel orange, cut into quarters and thinly slice across the sections, or cut into a pretty pattern of your choice.
1. Cream margarine and sugars until light and fluffy. Blend in vanilla. Beat in eggs one at a time.
2. Stir flour, salt, soda, and baking powder together thoroughly; blend into creamed mixture alternately with 1/2 cup sour cream and milk. Begin and end with flour.
3. Pour into greased and waxed paper-lined (grease the waxed paper lightly also) 13 x 9 x 2-inch pan. Bake in preheated 350-degree oven, 25-35 minutes or until done.
4. COOL COMPLETELY before removing from pan.
5. Cut cake in half to form 2 layers 6-1/2 by 9 inches. Spread 3/4 cup sour cream over layer, arrange orange slices on sour cream.
Top with second layer. Garnish each serving with additional sour cream and orange slices.
* The sour cream is an acquired taste. You may prefer to sweeten it with sugar or honey, or with a mix of half sour cream and half sweetened whipped cream.