Cream butter in a medium mixing bowl; gradually add 1/4 cup sugar, 1 tablespoon orange rind, and 1 egg. Stir in 1 1/4 cups flour. Spread mixture evenly in a greased 9-inch square baking pan. Bake at 350° for 20 minutes or until set.
Combine brown sugar and 2 eggs in a large mixing bowl, beating well. Add 2 tablespoons orange rind and juice; stir well. Stir in remaining 2 tablespoons flour and baking powder. Fold in coconut and pecans. Pour mixture evenly over baked crust. Bake at 350° for 20 to 25 minutes. Sprinkle with powdered sugar, and cut into 1 1/2- inch squares. Cool completely in pan.