Monster Cookies

published Jan 18, 2022
Monster Cookies Recipe

Chock-full of peanut butter, oats, and M&Ms, these soft cookies are a sweet crave-worthy treat.

Makes24 (2 3/4-inch) cookies

Prep15 minutes to 20 minutes

Cook13 minutes to 14 minutes

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monster cookies on a baking dish
Credit: Eric Kleinberg; Food Stylist: Kristina Vanni

Can’t decide between an oatmeal, peanut butter, or chocolate chip cookie? Monster cookies are the answer. These homey, soft-baked cookies are chewy from oats, packed full of protein from peanut butter, and not shy about the chocolate chip and M&M mix-ins, making them a great after-school snack or mid-afternoon treat.

Why Is It Called a Monster Cookie? 

I wrongly assumed that monster cookies would be large ones based on their name. But monster refers to how these are a Frankenstein of sorts, a bunch of beloved classic cookies mashed-up together into one delicious cookie. And while you can make them as large as you’d like, I prefer them to the size of a normal oatmeal or peanut butter cookie.

Credit: Eric Kleinberg; Food Stylist: Kristina Vanni

How Do You Make Monster Cookies from Scratch?

  1. Cream the butter and sugar. Beat softened butter with granulated and light brown sugar.
  2. Beat in the remaining wet ingredients. Beat in an egg, lots of creamy peanut butter, and some vanilla extract.
  3. Add the dry ingredients. Mix in quick rolled oats, flour, baking soda, and salt.
  4. Stir in the mix-ins. Mix in chocolate chips and M&M candies by hand.
  5. Scoop and bake. Scoop out onto baking sheets (no chill required) and bake at 350ºF until browned on the bottom.

Can You Use Instant Oatmeal in Monster Cookies?

Instant oats are ground up into too fine a powder for these cookies, but regular rolled oats are too big and the cookies end up very dry. Quick rolled oats, which are broken-up regular rolled oats, are the right kind of oats to use in monster cookies.

Baking from Frozen

Monster cookies freeze very well unbaked — just scoop out the dough onto a baking sheet and press each dough ball into a flat disk before freezing. Pressing the dough down helps the cookies to flatten out later when baked, and means you can bake the frozen dough balls straight from the freezer whenever you need a monster cookie fix.

Monster Cookies Recipe

Chock-full of peanut butter, oats, and M&Ms, these soft cookies are a sweet crave-worthy treat.

Prep time 15 minutes to 20 minutes

Cook time 13 minutes to 14 minutes

Makes 24 (2 3/4-inch) cookies

Nutritional Info


  • 8 tablespoons

    (1 stick) unsalted butter

  • 1

    large egg

  • 1 1/4 cups

    quick rolled oats

  • 1 cup

    all-purpose flour

  • 1 teaspoon

    baking soda

  • 3/4 teaspoon

    kosher salt

  • 1/2 cup

    granulated sugar

  • 1/2 cup

    packed light brown sugar

  • 2/3 cup

    smooth or chunky peanut butter

  • 1 teaspoon

    vanilla extract

  • 3/4 cup

    M&M candies, from 3 (1.69-ounce) bags

  • 1/2 cup

    semisweet or bittersweet chocolate chips


  1. Place 1 stick unsalted butter in the bowl of a stand mixer (or large bowl if using an electric hand mixer). Place 1 large egg and 2/3 cup peanut butter (if refrigerated) on the counter. Let all three sit at room temperature until the butter is softened.

  2. Arrange 2 racks to divide the oven into thirds and heat the oven to 350ºF. Line 2 baking sheets with parchment paper or silicone baking mats.

  3. Place 1 1/4 cups quick oats, 1 cup all-purpose flour, 1 teaspoon baking soda, and 3/4 teaspoon kosher salt in a medium bowl and stir until combined.

  4. Add 1/2 cup granulated sugar and 1/2 cup packed light brown sugar to the bowl of butter. Beat with the paddle attachment, starting on low speed and gradually increasing to medium speed, until lightened in color and fluffy, about 2 minutes total. Add the egg, 2/3 cup peanut butter, and 1 teaspoon vanilla extract, and beat on medium speed until combined, about 30 seconds.

  5. Add the flour mixture and beat on the lowest speed until just combined, about 15 seconds. Add 3/4 cup M&Ms and 1/2 cup semisweet or bittersweet chocolate chips, and stir by hand just until well-distributed.

  6. Scoop the dough out into 24 (scant 2-tablespoon) portions. Place 12 on each baking sheet, spacing them evenly apart.

  7. Bake for 8 minutes. Rotate the baking sheets between racks and from front to back. Bake until the edges are set and starting to brown, 7 to 8 minutes more. Let the cookies cool on the baking sheet at least 10 minutes to firm up before serving.

Recipe Notes

Make ahead: The dough balls can be formed and placed on one baking sheet. Press each dough ball down to flatten to about 2 inches wide and 1/2-inch tall (this will help it spread when baked), then freeze solid unbaked. Transfer to a freezer zip-top bag and freeze for up to 2 months. Bake from frozen, adding a minute or 2 to the bake time.

Storage: The cookies can be stored in an airtight container at room temperature for up to 3 days.