In a large pot, bring butter, sugar, milk, and cocoa powder to a boil, while whisking. Boil for one minute and remove from heat.
Add in the peanut butter and stir until smooth.
Now add the vanilla and oats and mix until well mixed.
Lay out a piece of parchment paper on a cookie sheet, or on a countertop. Spoon the mixture onto the parchment paper in cookie size portions. Allow to set or transfer to the refrigerator for faster cooling. Enjoy!