1-In a medium saucepan over medium heat, combine butter, sugar, milk, and cocoa powder. Whisk constantly until the butter melts, then bring the mixture to a boil and let it boil for 1 full minute without whisking.

2-Remove from heat immediately and stir in peanut butter and vanilla extract until fully combined.

3-Add oats and salt, then stir well. Let the mixture sit for 4-5 minutes, or up to 10 minutes if using natural peanut butter, to allow the oats to absorb moisture.

4-Line baking sheets with parchment paper or silicone mats. Drop tablespoon-sized mounds of dough about 2 inches apart and flatten slightly with the back of a spoon if desired.

5-Refrigerate for 30 to 60 minutes until the cookies set.

6-Store leftovers covered in the refrigerator for up to 1 week, or freeze for up to 3 months and thaw overnight before serving.