01 - Line two baking sheets with parchment paper or silicone baking mats and set aside.
02 - In a medium saucepan over medium heat, melt the butter. Add the granulated sugar and whole milk, stirring until fully incorporated.
03 - Bring the mixture to a gentle boil while stirring constantly. Once a rolling boil is reached, stop stirring and allow it to cook for exactly 1 minute.
04 - Remove the saucepan from heat. Immediately stir in the peanut butter, vanilla extract, and a pinch of salt until the mixture is completely smooth and uniform.
05 - Quickly fold the quick-cooking oats into the peanut butter mixture, stirring until every oat is thoroughly coated.
06 - Using a tablespoon or cookie scoop, drop rounded portions of the mixture onto the prepared baking sheets, spacing them about 1 inch apart.
07 - Allow the cookies to rest at room temperature for 10 to 15 minutes until fully hardened and set.
08 - Once firm, transfer the cookies to an airtight container for storage. Keep at room temperature for up to one week.