Mix sugar, milk, butter, and cocoa powder together in a medium-sized pot at medium-heat until it reaches a rolling boil.
Remove from heat.
Add peanut butter and vanilla extract.
Stir until peanut butter is smooth.
Add quick rolled oats and stir until thoroughly combined.
Scoop out a tablespoon of the mixture into your hand. Roll it into a ball.
Repeat with remaining mixture.
Serving Size 1 Ball
* Percent Daily Values are based on a 2,000 calorie diet. Your daily value may be higher or lower depending on your calorie needs.