Monster Cookie Bars Recipe

When a big ‘ol batch of Monster Cookies is just too much work.  Monster Cookie Bars.  One bowl, one baking sheet, made with much less mess, yet just as delicious alternative to Monster Cookies.

Monster Cookie Bars Recipe


  • 2 Cups Light Brown Sugar
  • 1 1/2 Cup White Sugar
  • 3/4 Cup Butter, softened
  • 1 1/2 Teaspoon Baking Soda
  • 3 Eggs
  • 1 Teaspoon Vanilla
  • 2 Cups Creamy Peanut Butter
  • 6 Cups Old Fashioned Oats
  • 1 Cup Semi Sweet Chocolate Chips
  • 1/2 Cup M&Ms
  • 1/2 Cup Reese’s Pieces



Begin by preheating the oven to 350* degrees. Then prepare a large baking (cookie) sheet with parchment paper.

Next, beat both sugars, butter and baking soda in a large mixing bowl until it is well blended then add eggs and vanilla to the bowl and mix until creamed. Add peanut butter and continue to mix the cookie dough until it is well blended.

Next use a wooden spoon to mix oats into the peanut butter mixture. Then add chocolate chips, M&Ms and Reese’s Pieces to the now dense dough.

Finally, press the dough onto the prepared baking sheet and at 350* degrees for 20-22 minutes.  Allow cool time before cutting this deliciousness into Monster Cookie Bars.  Enjoy!

*When you are in need of enough cookies to feed an Army, try my Monster Cookie Recipe – it makes 8 dozen.

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Monster Cookie Bars

Monster Cookie Bars Recipe

When a big ‘ol batch of Monster Cookies is just too much work. Monster Cookie Bars. Just one bowl & one deep cookie sheet required. No flour recipe.

Prep Time 20 minutes
Cook Time 20 minutes


  • 2 cups light brown sugar
  • 1 1/2 cups white sugar
  • 3/4 cup butter, softened
  • 1 1/2 teaspoon baking soda
  • 3 eggs
  • 1 teaspoon vanilla
  • 2 cups creamy peanut butter
  • 6 cups old fashioned oats
  • 1 cup semi sweet chocolate chips
  • 1/2 cup M&Ms candies
  • 1/2 cup Reese's Pieces


  1. Preheat oven to 350 degrees.  Prepare a large baking (cookie) sheet with parchment paper.

  2. Beat Sugars, Butter & Baking Soda in a large mixing bowl until well blended.  Add Eggs and Vanilla and mix until creamy.   Continue to use electric mixer and add Peanut Butter.  Once the mixture is well blended, use a wooden spoon to mix in Oats, Chocolate Chips, M&Ms and Reese’s Pieces.

  3. Press dough into pan and bake 20-22 minutes.  Allow cool time before cutting into bars.  Enjoy!

About Trish

When this sleep deprived self proclaimed tea addict is not creating content for this here blog, Trish can most often be found at the Little League field or watching a football game. Trish is a passionate volunteer, contract accountant, avid fan of the Dallas Cowboys and will only eat Oreos in pairs. She has two boys born sixteen years apart and her favorite place in the world is by her husband's side - preferably in a football stadium, at Disneyland or in San Diego.

8 thoughts on “Monster Cookie Bars Recipe

  1. I love to make bar cookies. Saves time! They look so yummy that I think I could eat the whole batch. Thanks for sharing at my Grandma Ideas Sharing Time link party.


  2. Oh my! This looks so fabulous! Pinned and tweeted. Please join us tonight at 7 pm, and party with us. I can’t wait to see your new masterpieces or amazing classics! Lou Lou Girls

  3. I love cookie bars and these look amazing! Thank you so much for linking up at Tasty Tuesday! This post has been pinned on the Tasty Tuesday Pinterest board! I love having you and can’t wait to see you next week!

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