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Halloween Monster Cookie Bars

The recipe

Halloween Monster Cookie Bars

  • Prep10 minutes
  • Cook22 minutes
  • Total32 minutes
  • Servings16

Ingredients

  • 2 cups all-purpose flour 250 grams
  • 1 ½ cups old-fashioned oats 120 grams
  • 1 teaspoon baking soda
  • ¼ teaspoon salt
  • ½ cup unsalted butter room temperature (113 grams)
  • ½ cup creamy peanut butter 128 grams
  • ½ cup granulated sugar 100 grams
  • ½ cup brown sugar lightly packed (100 grams)
  • 2 large eggs room temperature
  • 2 teaspoons vanilla extract
  • 1 cup Ghoul mix M&M’s divided (165 grams)
  • ½ cup semi-sweet chocolate chips divided (85 grams)
  • ½ cup peanut butter chips divided (120 grams)
  • Candy eyeballs to decorate optional

Instructions

  1. Preheat the oven to 350 degrees F. Line the bottom and sides of a 9×9 inch baking pan with parchment paper and set aside.
  2. Whisk together the flour, oats, baking soda, and salt in a medium bowl and set aside.
  3. In a large bowl, beat the butter, peanut butter, and sugars with a hand or stand mixer until light and fluffy.
  4. Scape the sides of the bowl and beat in the eggs and vanilla until well combined.
  5. Scrape the bowl again and add the flour and oat mixture. Mix until just combined, do not overmix.
  6. Set aside ¼ cup of M&Ms and two tablespoons each of the chocolate and peanut butter chips. Fold the remaining M&Ms, chocolate, and peanut butter chips into the cookie dough.
  7. Turn the cookie dough into the prepared pan and gently press into an even layer smoothing the top with a rubber spatula or the back of a spoon.
  8. Scatter the M&Ms, chocolate, and peanut butter chips that you set aside over the top of the cookie dough and gently press down.
  9. Bake for 22-28 minutes or until the edges have set and a toothpick inserted into the center comes out clean.
  10. Press the candy eyeballs into the cookie bars while they are warm, then allow them to cool completely in the pan before removing and cutting them into squares.
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