No-Bake Monster Cookie Bars

This post may contain affiliate links. Please read our disclosure policy.

No-Bake Monster Cookie Bars are one of my kids most favorite desserts. A thick layer of peanut butter cookie filled with M&M’s and topped with a delicious layer of chocolate. Grab a glass of milk, you’re gonna need it!

I love no-bake desserts, especially in the warmer months when I want to have a sweet dessert but don’t want to have to turn on the oven. We have made A LOT of them over the years and this is our newest additions. Scroll down to the bottom for my list of top five.

No Bake Monster Cookie Bars

These are soft and chewy and perfect for people who love the flavor combination of chocolate and peanut butter.

You can make some fun variations on this, too, by getting creative and adding in Reese’s Pieces instead of M&M’s or using white chocolate chips instead of regular. Have fun with it!

Ingredients You Will Need

  • Butter – to hold the bar ingredients together.
  • Sugar – regular and brown sugar.
  • Peanut Butter – the creamy kind.
  • Quick Oats – some left whole and some finely powdered in a food processor or a blender.
  • Vanilla – if you’ve got it, real vanilla is way better than imitation.
  • Salt
  • M&M’s – some of them go right into the bars and some go on top.
  • Chocolate Chips – to melt into our chocolate topping.
  • Heavy Whipping Cream – for the chocolate sauce.

Monster Cookie Bars Ingredients

How To Make Monster Cookie Bars

  1. Beat the butter and sugar together until it’s nice and creamy.
  2. Add in the peanut butter and keep mixing.
  3. Add the oats, salt and vanilla.
  4. Lastly, stir in the M&M’s.
  5. Press the dough into a parchment paper lined pan.
  6. Make the chocolate sauce by melting chocolate chips and heavy cream together.
  7. Pour over the oat mixture and sprinkle with extra M&M’s
  8. Let these cool in the fridge for a few hours then cut and serve.

No-Bake Monster Cookie Bars are a thick layer of peanut butter cookie filled with M&M's and topped with a delicious layer of chocolate.

More No-Bake Recipes To Try

Reese’s Peanut Butter Bars

Woolworth Cheesecake

Lemon Dessert Lasagna

Fruity Pebbles Cheesecake

Pineapple Dream Dessert

Monster Cookie Bars close up
No ratings yet

No-Bake Monster Cookie Bars

No-Bake Monster Cookie Bars are one of my kids most favorite desserts. A thick layer of peanut butter cookie filled with M&M's and topped with a delicious layer of chocolate.
Servings: 9
Prep: 10 minutes
Cooling Time: 3 hours
Total: 3 hours 10 minutes


  • Ingredients:
  • 6 Tablespoons butter softened
  • 6 Tablespoons sugar
  • ¼ cup brown sugar packed
  • ¾ cup creamy peanut butter
  • 6 Tablespoons quick oats finely powdered in a food processor
  • 1 tsp vanilla
  • ½ tsp salt
  • 1 ½ cups quick oats
  • 1 cup M and M’s ⅔ for bars, ⅓ for topping
  • 1 cup semi-sweet chocolate chips
  • 3 Tablespoons heavy whipping cream


  • Directions:
  • Line an 8x8 baking pan with parchment paper, leaving an extra inch on each side of the pan, then set the pan aside until the base of the bars is ready.
  • In a large bowl, or using a stand mixer, beat the butter and the sugars together. Once they have combined, add in the peanut butter and continue mixing for about 30 seconds.
  • Add the powdered oats, vanilla, salt, and oats, mixing the dough together. Stir in the ⅔ cup of M and M’s, until they are evenly distributed throughout the dough.
  • Press the mixture in the lined pan, spreading it evenly. Press it firmly into the bottom of the pan to avoid any gaps.
  • In a small, microwave safe bowl, melt the chocolate chips and the heavy whipping cream, for about one minute. Stir until the chips are completely dissolved and it is a thick chocolate syrup. Microwave for an additional 30 seconds if the chips aren’t melting.
  • Pour the chocolate sauce over the oat mixture, spreading it evenly. Sprinkle the remaining ⅓ cup of M and M’s over the top of the chocolate.
  • Cover and place in the refrigerator for about 2-3 hours, allowing the chocolate to set. Cut and serve.

Last Step:

Please leave a rating and comment letting us know how you liked this recipe! This helps our business to thrive and continue providing free, high-quality recipes for you.


Calories: 564kcal | Carbohydrates: 57g | Protein: 10g | Fat: 35g | Saturated Fat: 16g | Polyunsaturated Fat: 4g | Monounsaturated Fat: 11g | Trans Fat: 0.4g | Cholesterol: 30mg | Sodium: 303mg | Potassium: 313mg | Fiber: 5g | Sugar: 38g | Vitamin A: 369IU | Vitamin C: 0.2mg | Calcium: 69mg | Iron: 3mg

Leave a Review!

We LOVE hearing from you! Submit your question or comment here.

Your email address will not be published.

Your email address will not be published. Required fields are marked *

Recipe Rating:

I accept the Privacy Policy