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Kima

Monster Cookie Bars

These soft and chewy Monster Cookie Bars are packed with creamy peanut butter, quick-cook oats, colorful M&M's, and rich dark chocolate chips. They come together quickly in one pan and make an easy crowd-pleasing dessert for parties, holidays, bake sales, or an everyday sweet treat.
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Prep Time 7 minutes
Cook Time 18 minutes
Total Time 25 minutes
Servings: 20 bars
Course: Dessert
Cuisine: American
Ingredients Equipment Method Notes

Ingredients
  

Monster Cookie Bars
  • 1 cup brown sugar
  • 1 cup granulated sugar
  • 1/2 cup margarine
  • 3 eggs
  • 1 tbsp vanilla extract
  • 1 1/2 cups peanut butter creamy
  • 4 1/2 cups quick-cook oats
  • 1 tsp baking soda
  • 3 cups candy-coated chocolate candies such as M&M's, divided
  • 1 cup dark chocolate chips

Equipment

  • Electric mixer
  • Mixing bowl
  • Rimmed baking sheet
  • Parchment paper
  • Spatula

Method
 

Instructions
  1. Preheat the oven to 350°F (175°C).
  2. In the bowl of an electric mixer, combine the brown sugar, granulated sugar, and margarine. Beat until just combined.
  3. Add the eggs and vanilla extract and mix until combined.
  4. Add the creamy peanut butter and mix until incorporated.
  5. Slowly add the quick-cook oats and baking soda. Mix until everything is well combined.
  6. Fold in the dark chocolate chips and most of the M&M's, reserving a handful of candies for topping after baking.
  7. Spread the mixture evenly onto a nonstick or parchment-lined rimmed baking sheet. Press it into an even layer using your fingers or a spatula.
  8. Bake for 15–18 minutes, or until the bars are lightly golden.
  9. Immediately after removing the pan from the oven, gently press the reserved M&M's into the top of the warm bars.
  10. Allow the bars to cool completely in the pan before slicing into 20 bars and serving.

Notes

For the cleanest slices, allow the cookie bars to cool completely before cutting.
Do not overbake the bars. Remove them once the edges are golden so the centers stay soft and chewy.
Reserve a handful of M&M's and press them into the bars immediately after baking for a colorful finished appearance.