01 - Line two baking sheets with parchment paper to prevent sticking and set aside.
02 - In a medium saucepan, combine butter, sugar, milk, and salt. Bring to a rolling boil over medium heat, stirring occasionally. Boil for exactly 1 minute.
03 - Remove the saucepan from heat immediately. Stir in peanut butter and vanilla extract until the mixture is completely smooth.
04 - Add the quick-cooking oats to the saucepan and mix thoroughly to ensure all dry ingredients are coated with the wet mixture.
05 - Drop heaping tablespoons of the mixture onto the prepared baking sheets. Flatten slightly using the back of a spoon.
06 - Allow cookies to set at room temperature for at least 15 minutes, or until firm to the touch.