Pudding Chewy Brownies

1 small box chocolate pudding and
    pie filling (not instant)
1/2 cup unsifted flour
1/4 teaspoon baking powder
1/3 cup margarine
2/3 cup granulated sugar
2 eggs
1 teaspoon vanilla extract
1/2 cup nuts (optional)

Mix contents of pudding box with unsifted flour and baking powder.

Melt margarine. Remove from heat and add sugar. Beat in eggs, one at a time. Blend in vanilla extract and pudding mixture. Stir in nuts, if desired. Spread in greased 8-inch square pan. Bake at 350 degrees F for 35 minutes. Cool in pan, then cut into bars.