Snickerdoodle Coffee Cake

1 cup all-purpose flour
1 cup granulated sugar
1 teaspoon baking powder
1/2 teaspoon salt
1 tablespoon ground cinnamon
1/2 cup milk
1/4 cup melted butter
1 egg

Preheat oven to 400 degrees F. Grease and flour an 8- or 9-inch square pan.

Mix together the flour, sugar, baking powder, salt, cinnamon, milk, butter and egg. Pour into prepared pan. Sprinkle top heavily with sugar to form a crusty top. Bake for 25 minutes.

Best when served warm.