Spray a 9 x 13" baking pan with parchment paper. You can also line the pan with parchment paper for easier removal from the pan.
In a mixing bowl, beat butter until soft and creamy, 2-3 minutes.
1 cup butter
Add brown sugar and mix well.
2 ¼ cups brown sugar
Add vanilla.
1 tablespoon vanilla
Stir in eggs one at a time, mixing well after each egg.
3 eggs
Add flour to bowl and sprinkle baking powder and salt over the top of the flour. Mix well.
2 ½ cups flour, 2 teaspoons baking powder, ½ teaspoon salt
Measure out one cup of butterscotch chips and set aside. Add remaining butterscotch chips and chopped pecans the the mixing bowl.. Use a large silicone spatula or spoon to fold everything together.
1 bag butterscotch chips, 1 cup pecans
Place in pan and spread so the batter is evenly distributed.
Sprinkle with the butterscotch chips you set aside.
Bake in preheated 350°F oven for 30-35 minutes until golden brown.
Remove from oven and let cool before slicing.
Notes
Lining the pan with parchment paper is optional. If not using parchment, spray your pan with nonstick spray.
Make certain your butter is softened.
Fold in the chips and pecans with a large spoon or spatula.
Place reserved butterscotch chips on top of the dough. You could also add a few chocolate chips as well.
Bars are best sliced after they have cooled.
Place fully cooled bars in an airtight container and store at room temperature for 3-4 days.