I always get rave reviews for my "Symphony" brownies. Just use boxed brownie mix and mix according to directions on box. Spread half of mixture in pan, cover with Hershey's Symphony candy bars, then spread remaining mix on top and bake. Divine!
I have used several different brands of brownie mix. I've also used the plain candy bars and the ones with almonds and toffee. Oh my, so good. So good that I buy the family size brownie mix for a 9x13 pan instead of a small box for an 8x8 pan. LOL
Sometimes I even put chocolate frosting on top after they cool.