Preheat your oven to 350°F and lightly grease or line an 8x8 dish.
Mix the flour, baking powder, cinnamon, nutmeg, and salt in a small bowl.
In a large bowl, cream the butter and brown sugar for 3-5 minutes. Mix in the eggs one at a time, then stir in the vanilla. Add the dry ingredients and mix until combined.
The batter will be thick, so spread it evenly in the pan with a greased spatula or your hands. (wetting your fingertips with water will help the dough not stick to your hands)
Mix the sugar, cinnamon, and nutmeg in a small bowl, then sprinkle it over the batter.
Bake for 25-30 minutes, or until the top springs back when pressed. Cool before cutting. Enjoy!
