Line two baking sheets with wax paper.
Add the oats and peanut butter to a large bowl. Set aside.
2 1/4 cups old fashioned oats, 1 cup creamy peanut butter
In a large saucepan over medium heat, combine the granulated sugar, milk, butter, and cocoa powder. Bring to a roaring boil, while stirring consistently.
2 cups granulated sugar, 1/2 cup milk, 8 tablespoons butter, 1/2 cup cocoa powder
Boil for one minute while continuing to stir. (It is very important that it is at a full boil for one full minute.) Stir in the vanilla.
1 tablespoon vanilla
Remove from the heat, and working quickly, pour it over the oat and peanut butter mixture. Stir to combine.
Using a large spoon, spoon large spoonfuls of the mixture onto the waxed paper. Allow to cool completely. Eat immediately or store in an airtight container for up to a week.