Congo bars

My mother-in-law made a lot of wonderful desserts, she has passed away but I am lucky enough to have many of her hand written recipes.  Making her recipes bring back good memories for my whole family.  Tonight I made Congo bars, a family favorite.  They are ridiculously rich and so not good for you but isn't that the point of a dessert.  I hope your family enjoys these as much as mine do.

2/3 cup butter
1lb box of brown sugar
2 2/3 cup flour
2 1/2 tsp baking powder
1/2 tsp salt
3 eggs
1 cup chocolate chips
1 cup butterscotch chips

Melt butter with brown sugar in a pan over medium heat,  When completely melted remove from heat and let cool for 10 minutes.  Meanwhile, sift flour, baking powder and salt.  Add three eggs to the cooled sugar mixture, mix well.  Then add sugar mixture to flour mixture, batter will be thick.  Add chocolate and butterscotch chips.  Grease a 9x13 pan, pour mixture in the pan.  Bake at 350 degrees for 20-25 minutes until a toothpick inserted comes out clean.