1. Heat oven to 350°F. Grease 9-inch square baking pan.
2. Mix butter, sugar, pumpkin, and vanilla in bowl (I use my standing mixer). Stir together flour, cocoa, baking powder and salt; gradually add to mixer, on lower speed, until well blended. Spread batter evenly in prepared pan.
3. Bake 20 to 25 minutes or until brownies begin to pull away from sides of pan. Cool completely in pan on wire rack.