Prepare a baking sheet or large plate lined with parchment or wax paper, and set aside.
In a large saucepan, melt the sugar, butter, milk and cocoa powder. Bring to a rolling boil, and boil for 1-2 minutes. Remove the pan from heat.
Stir in the peanut butter and vanilla. Stir to combine. Once fully combined, stir in the oats.
Spoon out onto prepared parchment paper. Let cool completely before enjoying!
Notes
Oat check. Be sure you're using quick oats and not rolled oats for the best texture.Substitutions. Substitute your preferred nut butter in place of peanut butter. You can use non-dairy milk and plant-based butter. Watch the pot boil. If you boil the mixture for too long, the cookies may turn out crumbly. If you under-boil the mixture, they will be too soft and won't set properly. Aim for 1-2 minutes, no more and no less.