With this simple brownie in a cup recipe, you can have a easy yummy DIY brownie in UNDER 5 MINUTES! It pairs perfectly with a cup or home brewed @Starbucks. I don’t know about you, but sometimes I crave for something sweet and chocolatey. The only problem with cooking or baking a brownie from scratch is the cleanup afterwards. The hack and solution to this cleanup problem is baking it in the mug!