Grease bottom and sides of 13 x 9 inch Pyrex dish.

STEP 1:

1 (6 oz.) pkg. butterscotch pieces
1/2 c. butter

Melt this mixture in a heavy 3 quart saucepan over medium heat, stirring constantly. Remove from heat; cool to lukewarm.

STEP 2:

1 1/2 c. flour
2/3 c. brown sugar, packed
2 tsp. baking powder
1/2 tsp. salt
1 tsp. vanilla
2 eggs, beaten

Mix dry ingredients and stir into butterscotch mixture in saucepan. Add vanilla and beaten eggs and mix well.

STEP 3:

2 c. miniature marshmallows
1 (16 oz.) pkg. semi-sweet chocolate pieces
1 c. chopped nuts, if desired

Fold into butterscotch batter just until blended, about 5 strokes. Spread into prepared pan and bake at 325 degrees for 25 to 30 minutes. DO NOT OVERBAKE! Center will be jiggly, but become firm upon cooling. Makes approximately 24 bars.