Monster Peanut Butter-Oatmeal-Chocolate Chip Cookies

Monster Cookies

This cookie is the Frankenstein’s monster of the cookie world. One part oatmeal cookie, one part peanut butter cookie, and one part chocolate chip cookie, it’s many things to many people. We re-created this rather large, chewy cookie as an homage to the Monster Cookies we remember eating in grade school, only our version is slightly less sweet and a whole lot better.–Matt Lewis and Renato Poliafito

LC Monster Mash Note

This recipe creates a mash up of sorts from quite a lot of various ingredients that may, at first blush, collectively seem quite monstrous. Yet what results is not to be missed by anyone who feels their soul’s deepest desire can be found in chewy, substantial cookie goodness.

Monster Peanut Butter-Oatmeal-Chocolate Chip Cookie Recipe

  • Quick Glance
  • 20 M
  • 50 M
  • Makes 36 cookies


  • 1/2 cup all-purpose flour
  • 1 tablespoon baking soda
  • Pinch of salt
  • 5 3/4 cups rolled oats
  • 3/4 cup cold unsalted butter, cut into cubes
  • 1 1/2 cups firmly packed light brown sugar
  • 1 1/2 cups granulated sugar
  • 5 large eggs
  • 1/4 teaspoon vanilla extract
  • 2 cups creamy peanut butter
  • 6 ounces bittersweet chocolate, cut into chunks
  • 1 cup (6 ounces) M&M’s (regular or peanut)


  • 1. In a large bowl, whisk together the flour, baking soda, and salt. Add the oats and stir until the ingredients are evenly combined.
  • 2. In the bowl of an electric mixer fitted with the paddle attachment, beat the butter until smooth and pale in color. Add the sugars and mix on low speed until just incorporated. Do not overmix.
  • 3. Scrape down the bowl and add the eggs, 1 at a time, scraping down the bowl and beating until smooth after each addition, about 20 seconds. Add the vanilla and beat until just incorporated.
  • 4. Scrape down the bowl and add the peanut butter. Mix on low speed until just combined. Add the oat mixture in 3 additions, mixing on low speed until just incorporated.
  • 5. Use a spatula or wooden spoon to fold in the chocolate chunks and M&Ms. Cover the bowl tightly and refrigerate for 5 hours.
  • 6. Preheat the oven to 375°F (190°C). Line 2 baking sheets with parchment paper.
  • 7. Use an ice cream scoop to plop the dough in 2-tablespoon-size balls onto the prepared baking sheets, spacing them about 2 inches apart. Bake for 12 to 15 minutes, switching and reversing the sheets halfway through the baking time, until the cookies just begin to brown. Let the cookies cool on the pans for 8 to 10 minutes before transferring them to a wire rack to cool completely. The cookies can be stored in an airtight container for up to 3 days.
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