In a large saucepan, combine 2 cups of granulated sugar, ½ cup of whole milk, ½ cup of unsalted butter, and ⅓ cup of unsweetened cocoa powder. Heat over medium heat, whisking until smooth. Bring to a rolling boil for about 1 minute.

After exactly 1 minute of boiling, promptly remove the saucepan from heat and let the mixture cool slightly.

Once cooled slightly, stir in 3 cups of quick oats and ½ cup of creamy peanut butter until well combined.

Pour in 1 teaspoon of pure vanilla extract, stirring well to distribute evenly.

Drop spoonfuls of the mixture onto parchment or wax paper, spacing them a couple of inches apart.

Let the cookies sit at room temperature for 15-30 minutes to set.