These cupcakes are rich, moist, and bursting with chocolate peanut butter flavor. I freaking love these cupcakes. This easy homemade peanut butter frosting is a far cry from that dull, overly sweet, tooth-ache-in-a-jar frosting you’re used to finding at the store. The best part? It’s made with simple, easy to find ingredients. For this frosting you’ll need butter, peanut butter, vanilla extract, salt, and confectioners’ sugar. That’s it! No yucky or hard to pronounce ingredients here.