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Small-batch Monster Cookie Bars

Small-batch peanut butter Monster cookie bars made with oats, M&M's, and chocolate chips. Baked in a loaf pan and cooled before slicing.
Prep Time10 minutes
Cook Time15 minutes
Total Time1 hour 11 minutes
Servings: 6 servings

Ingredients

Ingredients

  • 3 tablespoons 42 g salted buttersoftened*
  • 1/2 cup 132 g peanut buttercreamy or chunky*
  • 1/3 cup 67 g granulated sugar
  • 1/3 cup 67 g brown sugar
  • 1 large egg
  • 1/2 teaspoonvanilla extract
  • 1 1/2 cups 130 g quick/instant oats*
  • 1/2 teaspoonbaking soda
  • 1/2 cup 85 g M&M’splus more for topping
  • 1/3 cup 56 g chocolate chips

Instructions

Instructions

  • Preheat the oven to 350°F. Lightly grease and line a loaf pan with parchment paper (leave some overhang to lift the bars out).
  • In a medium bowl, combine 3 tablespoons (42 g) salted butter (softened), 1/2 cup (132 g) peanut butter (creamy or chunky), 1/3 cup (67 g) granulated sugar, and 1/3 cup (67 g) brown sugar. Beat or mix until well combined and slightly lightened in color, about 1 minute.
  • Add 1 large egg and 1/2 teaspoon vanilla extract. Mix until fully incorporated.
  • Add 1 1/2 cups (130 g) quick/instant oats and sprinkle 1/2 teaspoon baking soda over the top. Mix until the oats and baking soda are evenly incorporated.
  • Fold in 1/2 cup (85 g) M&M’s and 1/3 cup (56 g) chocolate chips with a wooden spoon or spatula until evenly distributed.
  • Transfer the mixture to the prepared loaf pan and press it into an even layer. Sprinkle a few extra M&M’s on top if desired.
  • Bake at 350°F for 15 to 18 minutes, until the edges are lightly browned and the center still looks pale and slightly underdone. Do not overbake.
  • Remove from the oven and let the bars cool in the pan for about 45 minutes to firm up.
  • Use the parchment overhang to lift the bars from the pan, transfer to a cutting board, slice into bars, and serve.

Equipment

  • 1-pound loaf pan
  • Parchment Paper

Notes

Notes
Store bars at room temperature in an airtight container for 3 to 4 days or freeze in a freezer bag for up to 2 months.
*If using unsalted butter, add 1/8 teaspoon of salt along with the oats and baking soda.
*These bars have not been tested with natural peanut butter.
*Old-fashioned/rolled oats may also be used.
Nutritional information is for 8 servings.