Cream the 1/2 cup margarine and the 1 cup sugar.

Combine flour, baking powder and salt. Add flour mixture alternately with egg and milk mixture to creamed ingredients. Spread batter in greased and floured 13 x 9-inch pan. Spread pie filling on batter.

Mix the 1/2 cup sugar and the 1/2 cup flour. Cut in margarine until mixture is size of small peas. Spread over pie filling; bake at 350 degrees F for 40 to 50 minutes or until cake tests done.