Seriously decadent and oh so delicious! You won't want to share!
Preheat oven to 350°F.
Pour brownie batter into a prepared 9x13 baking dish and bake at 350°F for 30-35 minutes, or until an inserted toothpick is removed mostly clean. (a few crumbs is good!)
Finish dessert by sprinkling Reese's Peanut Butter Cups over top.
Refrigerate for at least 2 hours or up to overnight. (If refrigerating overnight, cover first.)