In a medium saucepan, combine peanut butter, granulated sugar, brown sugar, cocoa powder, and milk over medium heat.
Stir the mixture continuously until it starts to bubble.
Remove the saucepan from heat and stir in vanilla extract.
Add quick oats and mix until fully combined.
Fold in chocolate chips if desired.
Prepare a baking sheet by lining it with parchment paper.
Use a cookie scoop or spoon to drop dollops of the mixture onto the baking sheet.
Allow cookies to cool at room temperature for about 30 minutes.
Once set, transfer cookies to an airtight container.
Enjoy your delicious no bake cookies!