Stovetop Cooking: Combine the oats, milk (or water), cocoa powder, and salt in a small pot and bring to a boil over medium high heat. Reduce heat to medium low and cover for 10 minutes, stirring occasionally. Remove from heat and stir in the sweetener of choice. Spoon peanut butter on top, and mix throughout.
Microwave Cooking: Put oats into a microwavable-safe bowl an add in 2/3 cup of milk (or water). Microwave for 2- 2 1/2 minutes, and stir in cocoa powder, sweetener, and salt until everything is well combined. Spoon peanut butter on top, and mix throughout.