Butterscotch-Cashew Bars  

Ingredients
1 box plain yellow cake mix
1/2 c. butter, melted
1/4 c. brown sugar
2 eggs
1 tsp. vanilla
1 c. cashews, chopped (or other nut)
1 c. butterscotch chips (or any chip, really)  

Directions
Preheat oven to 350F.  Grease a 9x13 baking dish.  Set aside. 
Combine cake mix, butter, brown sugar, eggs, and vanilla in a large mixing bowl, beating on low speed for 1 minute.
Scrape down sides of bowl and beat for 1 more minute. Spread batter evenly in prepared pan. Sprinkle with nuts and butterscotch chips. 
Bake for 25-30 minutes or until toothpick inserted near center comes out clean, and top is lightly browned.   And as I finished typing that out, I went to go cut them and put them in a container while still slightly soft and warm...and yeah they're good. ;)
Salty-sweet, and pretty rich.  If you want less salty though, just go with unsalted nuts, as especially cashews tend to be quite salty