1. Preheat oven to 350° F.
2. Grease the bottom and sides of a shallow 15x10 baking pan. Add 3 tablespoons flour and shake pan until flour covers the bottom and sides. Discard excess flour.
2. Sift 2 cups flour and baking powder together in a small bowl and add salt.
3. In a separate bowl, beat sugar and butter until well blended.
4. Beat in eggs and vanilla until creamy.
5. Gradually mix in flour mixture until well blended.
6. Stir in chocolate and butterscotch chips.
7. If you are adding nuts, stir them in now.
8. Pour mixture into the shallow greased 15 x 10 pan.
9. Bake for 25 minutes or until golden brown.
10. Allow to cool.
11. Cut into 3 long rows and cut the rows into 12 pieces each. That gives you 36 brownies.
13. Store uneaten brownies in an airtight container or plastic bag.