Preheat the oven to 350˚.
Melt the butter in a pan.
Add the brown sugar, and stir until it is dissolved and well-blended.
Stir in the oats, salt, and baking powder.
Spread in an 8×8-inch baking pan.
Bake for 20 – 25 minutes, until lightly browned.
Cool in the pan for about 15 minutes; cut into squares while still warm. Allow to cool completely before serving.
