Monster Cookie Bars

5 from 11 votes

Monster Cookie Bars are a holiday favorite and these delicious chewy bars are made with old-fashioned oats, peanut butter, chocolate chips, and M&M’s.

Prep Time10

Cook Time18

Total Time28

Course: Dessert

Cuisine: American

Keyword: cookies, holiday, M&M’s, Monster, oatmeal, peanut butter, treat

Servings: bars

Calories: 699kcal

Author: Dana

Equipment

Ingredients

½ cup butter softened
¾ cup brown sugar packed
½ cup granulated sugar
1 egg
½ teaspoon salt
1 teaspoon vanilla extract
1 cup creamy peanut butter
½ cup all purpose flour
½ teaspoon baking soda
1 ¾ cups old fashioned oats
1 cup semisweet chocolate chips
1 cup M&Ms

Instructions

Preheat the oven to 350℉
Line a 9x9 baking dish with parchment paper and lightly grease the sides.
Using a hand mixer or stand mixer on medium speed, cream together butter and both sugars.
Add in the egg and vanilla, mixing well.
Mix in peanut butter until smooth.
Combine the flour and the baking soda together and then mix it into the peanut butter mixture.
Blend in the old fashioned oats.
Stir in M&M’s and the chocolate chips.
Evenly spread mixture into the 9x9 baking dish.
Sprinkle the top with M&M’s and additional chocolate chips then gently press them down into the top of dough.
Bake for 18-20 minutes. The outer parts of the dish should be lightly brown.
Allow to cool completely before cutting into squares and removing from the pan to prevent crumbling.
Store in an airtight container.

Notes

The bars must cool completely before removing them from the pan because they will crumble and fall apart. Allowing them to cool will help them keep their shape.

Nutrition