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–+ servings
all the chewy monster cookie bars cut into squares.

Monster Cookie Bars

Brooke Homec
Monster Cookie Bars are a peanut butter oatmeal cookie bar loaded with m&m's, chocolate chips and an extra layer of peanut butter drizzled through the middle. They're so chewy and bursting with flavor!
5 from 18 votes
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Prep Time 10 minutes
Cook Time 30 minutes
Course Dessert
Cuisine American
Servings 16
Calories 297 kcal

Ingredients
 

  • ¾ cup (170.25 g) butter
  • ¼ cup (64.5 g) creamy peanut butter
  • ¾ cup (165 g) brown sugar light is fine too
  • 1 large egg
  • 1 tablespoon vanilla
  • ½ teaspoon (0.5 teaspoon) salt
  • ½ teaspoon (0.5 teaspoon) baking soda
  • 1 cup (140 g) all-purpose flour
  • 1 cup (81.08 g) old fashioned oats
  • ½ cup (118.29 g) mini m&m's plus more for topping
  • ½ cup (90 g) semi sweet chocolate chips
  • ½ cup (113.4 g) peanut butter for drizzling
  • flaked sea salt

Instructions
 

  • Preheat the oven to 350 F. Grease a 8x8 pan with cooking spray, or line with parchment.
  • In a large mixing bowl fitted with the paddle attachment, cream together butter, ¼ cup of peanut butter and brown sugar until light and fluffy. Add egg and vanilla and mix in.
  • Add the salt, baking soda, flour and oats, mixing until combined. Fold in ½ cup of mini m&m's.
  • Press half the dough onto the bottom of the 8x8 pan. Bake for 10 minutes. You will save the remaining half of the dough for topping.
  • Warm a ½ cup of peanut butter in a microwaveable safe bowl.
  • Top the warm, cooked bottom layer of the bars with chocolate chips and then drizzle with peanut butter.
  • Place dollops of remaining dough on top, don’t worry about it spreading evenly over the top. Sprinkle extra m&m's on top. Bake an additional 16-18 minutes. Remove from oven and sprinkle with flaked salt. Allow to cool before cutting.

Notes

You can double this recipe and bake it in a 9x13 pan instead. When doing so add 2-3 minutes to each part of the baking.
I have given both cups and grams as measurements. Grams will be more precise, especially when measuring flour. If you don’t have a kitchen scale, no problem! Just lightly spoon flour into your measuring cup to insure its not packed in there. Light and fluffy is the key.

Nutrition

Calories: 297kcalCarbohydrates: 29gProtein: 5gFat: 18gSaturated Fat: 9gPolyunsaturated Fat: 2gMonounsaturated Fat: 6gTrans Fat: 0.4gCholesterol: 24mgSodium: 231mgPotassium: 139mgFiber: 2gSugar: 17gVitamin A: 283IUVitamin C: 0.04mgCalcium: 32mgIron: 1mg
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