Heat oven to 350F. Grease 13x9-inch pan.

In large bowl, beat sugar and margarine until light and fluffy. Add eggs and vanilla; beat well.

Combine flour, baking powder, baking soda and salt. Alternately add flour mixture and sour cream to sugar mixture, beating well after each addition.

Spread 1/2 of batter in prepared pan; top with apple sauce. Drop spoonfuls of remaining batter over apple sauce.

In small bowl, combine topping ingredients. Sprinkle over batter.

Bake at 350F for 50 to 60 minutes or until toothpick inserted in center comes out clean.

Yields 16 servings.

streusel-topped coffee cake with freshly brewed coffee for a mid-morning break.