Preheat oven to 350 degrees F and grease an 8×8 baking dish.
Add butter to a large saucepan over medium- high heat. Once butter begins to boil, continuously swirl pan to prevent burning. Continue until butter darkens to an amber color, then remove from heat.
Add the brown sugar to the warm butter and stir until fully integrated. Mix in the eggs and vanilla.
Add the flour, baking powder, and salt to the wet ingredients. Stir until combined.
Fold coconut into the batter and then transfer to the prepared baking dish.
Bake for 40-45 minutes, covering with foil for the last 10 minutes. Let bars fully cool before slicing.