Mix together granulated sugar, 2 tablespoons flour, salt and cinnnamon in a large mixing bowl.

Peel and core apples. Cut into ¼-inch slices and toss in sugar mixture until fully coated. Place in the bottom of an 8 or 9-inch baking pan.

Combine oatmeal, baking soda, brown sugar, baking powder and remaining cup of flour. Work softened butter into mixture with a fork. Mixture will become crumbly.

Sprinkle mixture over apples.

Bake in 350°F oven for 35 minutes.