Monster cookies are slightly crisp on the outside, and soft and chewy in the center. They are loaded with peanut butter, oats, M&M candies, AND chocolate chips! Big monster cookies win every time!

Give me ALL the oatmeal in my cookies! I love the added texture it adds. If you’re like me, try these no-bake cookies, our favorite oatmeal fudge bars, or stick with a classic oatmeal cookie recipe.

Monster Cookies

Monster cookies start with a classic cookie recipe but the add-ins are where it’s at! They are loaded with peanut butter, chocolate, and oatmeal resulting in the best chewy texture! Plus, they have chocolate chips AND M&M’s! What’s better than a cookie that has both?! Everyone goes crazy over this recipe and you’ll be asked to make them again and again. My kids love these cookies because I make them nice and BIG…just what a monster cookie should be!

Cookies are a staple food at our house and it’s always fun to switch it up! Try some more favorites like these iced oatmeal cookies, these yummy clothespin cookies, or these brookies!

Ingredients to Make Monster Cookies

These cookies use classic ingredients that you probably already have in your pantry! I might need to run to the store and grab some M&M’s but it’s so worth it! Check out the recipe card at the bottom of the post for the exact measurements.

• Unsalted Butter: Butter provides richness and a buttery flavor.
• Granulated Sugar: Adds sweetness to the dough.
• Light Brown Sugar: Brown sugar adds a warm caramel undertone, enhancing sweetness and creating a chewy texture in the cookies.
• Creamy Peanut Butter: You will LOVE the added peanut butter flavor in this cookie.
• Eggs:  Use room-temperature eggs.
• Vanilla Extract: Vanilla is always a must in cookie dough.
• All-Purpose Flour: Gives structure to the cookies.
• Old-Fashioned Rolled Oats: Adds the best texture to the cookies.
• Salt: This enhances all of the flavors in this cookie recipe.
• Baking Powder and Baking Soda: These help the cookies rise and make them light and soft.
• Mini M&M Candies: It’s not a monster cookie if it doesn’t have M&M’s!!
• Mini Semi-Sweet Chocolate Chips: The more chocolate the better if you ask me!

Monster Cookie Recipe

We love baking on the weekends at our house! This is the perfect recipe to let them help you make. They love making monster cookies because the name is fun and there are lots of ingredients they can easily measure by themselves.

1. Preheat Oven/ Prepare Pan: Preheat the oven to 350 degrees Fahrenheit and line 2 baking sheets with parchment paper.
2. Beat the Butter and Sugars: Use a hand mixer or a stand mixer fitted with a paddle attachment to beat the butter, sugar, and brown sugar together on medium-high speed for 3-4, until light and fluffy.
3. Add the Peanut Butter, Eggs, and Vanilla: Add the peanut butter and mix until combined. Add the egg and vanilla and mix again until combined. Scrape down the sides and bottom of the bowl as needed to make sure everything is fully incorporated.
4. Combine the Dry Ingredients: In a medium bowl whisk together the flour, oats, salt, baking powder, and baking soda.
5. Mix the Wet and Dry Ingredients: Add the dry ingredients to the wet mixture and mix until just combined. Stir in M&M’s and chocolate chips by hand.
6. Scoop the Cookie Dough: Use a medium-sized cookie scoop to scoop the dough onto the prepared baking sheets, leaving at least 2 inches between them.
7. Bake: Bake for 9-11 minutes but do not overbake them! They will look just set on the edges and a little doughy in the center.
8. Cool: Remove them from the oven and allow them to cool on the pan for 5 minutes before transferring to a cooling rack.

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