No-Bake Chocolate Oatmeal Cookies are an old-timey favorite and one of the easiest and most delicious cookies you'll ever make. I think pretty much everyone has had these cookies at one time or another and pretty much everyone loves them.
In a large saucepan, combine the butter, cocoa powder, sugar, and milk,
Stir well and bring to a boil over medium heat. Boil for 90 seconds, stirring occasionally.
Remove from the heat and stir in the oats, peanut butter, and vanilla.
Drop by heaping tablespoonfuls onto baking sheets lined with wax paper or parchment paper. Let cool to set.
Notes
Set a timer and be sure to boil the chocolate mixture for precisely 90 seconds. If you don't boil long enough, it is likely your cookies won't set up. If you boil too long they will be dry and crumbly.