Monster cookie bars are sweet and salty, chewy and chocolatey! From
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Monster Cookie Bars Stuffed with Reeses

Chewy monster cookie bars are sweet and salty with lots of peanut butter flavor. Super easy to make, too!
Prep Time 5 minutes
Cook Time 45 minutes
Total Time 50 minutes
Servings 28 bars
Author Marye Audet-White


  • 3 cups flour
  • 2 cups quick oats
  • 1 teaspoon of salt
  • 1 cup butter softened
  • 1 cup peanut butter
  • 1 1/2 cups sugar
  • 1 1/2 cups brown sugar
  • 2 teaspoons baking soda
  • 2 teaspoons water
  • 4 eggs
  • 2 teaspoons vanilla
  • 1 1/2 cups M&M's
  • 1 cup broken mini pretzels
  • 1/2 cup dark chocolate chips
  • 28 Cups Reese's Peanut Butter Miniatures wrappers and papers removed.


  • 1 cup white chocolate chips
  • 1 tablespoon white vegetable shortening
  • 2 tablespoons peanut butter


  • Preheat the oven to 350F.
  • Grease a 13x9-inch baking dish.
  • Mix the flour, oats, and salt.
  • Set aside.
  • Blend the butter and peanut butter until completely combined.
  • Add the sugar and brown sugars.
  • Beat well.
  • Blend the baking soda and water until the baking soda is dissolved.
  • Pour into the butter mixture.
  • Add the eggs, one at a time, beating well after each one.
  • Stir in the vanilla.
  • With the mixer on low, slowly add the flour mixture beating until well blended.
  • Stir in the M&Ms, mini pretzels, and chocolate chips.
  • Spread a thin layer of the dough on the bottom of the baking pan.
  • Arrange the peanut butter cups evenly over the dough.
  • Carefully top with the remaining dough, pressing down slightly to make sure there are no holes.
  • Bake for 40 to 45 minutes, or until done.
  • Let cool.
  • Drizzle on the glaze.
  • Cool completely before cutting.


  • Melt the white chocolate chips and shortening on 50% power for 2 minutes (or until melted) stirring every 30 seconds.
  • Stir in the peanut butter until mixture is totally combined and smooth.


Freeze well. Are better when completely cool or even the next day.