Preheat the oven to 350 degrees F. Spray an 8 x 8 x 2 inch baking pan with nonstick cooking spray.
In a medium bowl, combine the flour, nutmeg, 1/2 teaspoon cinnamon, and salt.
In another medium bowl, beat 3/4 cup sugar and the margarine together until fluffy with an electric mixer at medium speed, about 2 minutes. Beat in the egg and milk until smooth, about 1 minute.
Add the flour mixture to the margarine mixture in thirds, beating until smooth, (about 2 minutes). With a large spoon, stir in the apples until evenly distributed. Spread the batter in the prepared pan.
In a small bowl, combine the remaining teaspoon of sugar and remaining 1/2 teaspoon cinnamon for the topping, then sprinkle evenly on the batter. Bake until brown and the sides start to pull away from the sides of the pan, approximately 40-45 minutes.