This is what it looked like before I baked it and without the streusel topping. Gorgeous!
1 cup all-purpose flour
1 teaspoon Baking powder
¼ teaspoon baking soda
1/8 teaspoon salt
¼ cup margarine or butter, softened
½ cup sugar
1 teaspoon vanilla
3 tablespoons nonfat plain yogurt
2 cups thinly sliced, unpeeled apples
¼ cup all-purpose flour
2 tablespoons brown sugar
½ teaspoon cinnamon
2 tablespoons margarine or butter
Preheat oven to 350 F. Spray an 8- or 9- inch round spring-form or 8-inch square pan with non-stick spray.
Combine flour, baking powder, baking soda, and salt, mix well. Beat margarine and sugar until light and fluffy. Add egg and vanilla, blend well. Alternately add flour mixture and yogurt to margarine, beat well after each addition. Spread batter in pan and arrange apple slices over batter.
In a small bowl, combine all topping ingredients except margarine. With pastry blender or fork, cut in margarine/butter until crumbly. Sprinkle topping evenly over apples.
Bake at 350 F for 30-35 minutes or until toothpick inserted in center comes out clean. Cool 10 minutes. If desired, remove from pan.