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Monster Cookies

Yields 30 cookies     adjust servings

Monster Cookies! They're watching youuuu!!! Chewy and tender peanut butter oatmeal cookies, studded with M&Ms and candy eyes to make Monster Cookies extra spooky for Halloween! They are soft cookies that are really easy to throw together.  


  • 1 cup (2 sticks) salted butter, softened
  • 1 cup dark or light brown sugar
  • 3/4 cup white sugar
  • 1 cup peanut butter (creamy or chunky)
  • 2 eggs
  • 1 teaspoon vanilla
  • 1 and 1/2 cups flour, spooned and leveled
  • 2 teaspoons baking soda
  • 1 teaspoon salt
  • 1 cup quick oats
  • 1/2 cup old fashioned oats
  • 2 cups M&Ms, plus more for topping*
  • candy eyes, optional


  1. In a large bowl or stand mixer, beat the butter for 2 minutes, scraping the sides and bottom.
  2. Add the brown sugar, white sugar, and peanut butter. Beat until incorporated.
  3. Add 2 eggs and vanilla. Beat well, scraping sides and bottom.
  4. Add flour but don't mix it in. Use a small spoon to stir the baking soda and salt into the flour, then beat in gently. There should still be flour streaks.
  5. Add the quick oats, old fashioned oats, and M&Ms. Stir until incorporated but do not over mix.
  6. Cover the bowl and chill the dough in the fridge for 1-3 hours (or overnight).
  7. When the dough is chilled, preheat the oven to 350 degrees F. Line 2 baking sheets with silicone baking mats or parchment paper.
  8. Use a large cookie scoop to shape the cookies. (You want cookie dough balls about 2 inches across.) Place on the baking sheet at least 2 inches apart from each other.
  9. Bake the cookies at 350 for 10-12 minutes until the centers are alllmost done being shiny. The edges should be firm. Do not over bake.
  10. Immediately press more M&Ms and a few candy eyes into the top of each cookie. If you want really tall, chewy cookies, take a spoon and push the edges in toward the middle on each cookies. Check this post for more details.
  11. Let cool on the sheet for 5 minutes before removing to a cooling rack. You should definitely eat at least one of these warm. Or maybe 2 or 3. 
  12. Store covered on the counter!