Line 2 baking sheets with parchment paper.

In a medium saucepan over medium high heat, combine butter, sugar, milk and cocoa powder. Cook stirring frequently until it starts to boil. Let the mixture boil for 1 minute until the sugar has dissolved.

Remove from heat and stir in peanut butter, vanilla and oats until everything is fully combined.

Using a medium size cookie scoop or 2 tablespoons drop the mixture onto the lined baking sheets (15-20 per sheet).

Let the cookies rest until set for 1 hour at room temperature. You want to be able to easily remove them from the parchment paper.

Store the cookies in an airtight container or Ziploc bag at room temperature or refrigerator.