Line two baking sheets with parchment or wax paper; set aside.

In a saucepan over medium heat, melt the butter. Whisk in milk, sugars, and cocoa powder stirring constantly; bring mixture to a boil stirring constantly.

Once mixture begins to boil, boil for exactly 1 minute (Use a timer, it’s important not to over or under boil) then remove from heat.

Whisk in peanut butter and vanilla extract, stirring until peanut butter is completely melted into the mixture.

Using a wood spoon, stir in oats until well coated. Drop cookie mixture by 1 1/2 to 2 tablespoonful size onto prepared baking sheet.

Allow cookies to cool before serving. The cookies will harden as they cool. To speed things up, refrigerate them until set.