Monster Cookies

Monster Cookies

Monster cookies are everything good that there is about cookie-baking and candy-eating. They are sometimes referred to as “kitchen sink cookies” because at first glance it seems that just about everything but the kitchen sink is thrown into these cookies. Peanut butter, oats, chocolate chips, M&M’s, Reese’s Pieces… They are basically the Peanut Butter-Oatmeal Chocolate Chip Cookies on steroids. Not only more ingredients, but bigger too. The monster cookies go the no-holds-barred route when it comes to size. And when it comes to cookies (at least in my book), bigger is always better. Which is probably why the Thick and Chewy Chocolate Chip Cookies and the Chewy Oatmeal-Raisin Cookies are two of my absolute favorites. Big, thick, chewy. Love ’em. And I love these.

Monster Cookies

The fabulous thing about these cookies is that they are totally adaptable to your tastes and you can go hog wild in creating the perfect cookie for you. The original recipe calls for butterscotch chips (not Reese’s Pieces) but with peanut butter in the batter, and because I have a serious love affair with Reese’s Pieces, I decided to nix the butterscotch chips for Reese’s Pieces. You could also use peanut butter chips, which would be fabulous as well. Really, whatever you like, throw in! I think chopped nuts would be great too. I somewhat included nuts by using chunky peanut butter instead of creamy, but that’s really a personal preference. I briefly considered peanut M&M’s but figured they would be too big for the cookies (probably a good call). The key here is to make the monster cookies your monster! Dig deep and channel that inner mad scientist.

What would your ultimate monster cookie have in it?

(I looked high and low for red, white and blue M&M’s to use in these – they would be great to take to a 4th of July picnic this weekend! – but I couldn’t find any.)


Monster Cookies

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Monster Cookies


3 eggs
1 cup granulated sugar
1 cup light brown sugar
1 teaspoon vanilla extract
1 teaspoon corn syrup
2 teaspoons baking soda
1 teaspoon salt
½ cup (4 ounces, or 1 stick) unsalted butter, melted
1½ cups chunky peanut butter
4½ cups rolled oats
½ cup all-purpose flour
¾ cup chocolate chips
¾ cup Reese's Pieces
¾ cup M&M's


1. Preheat the oven to 350 degrees F. Line three baking sheets with parchment paper or silicone baking mats. (If you don't have three baking sheets, just be sure to cool the ones coming out of the oven before placing more cookie dough on them. If I'm short on sheets I will run them under cold water to cool them down.)

2. In a large mixing bowl, stir together the eggs, both sugars, vanilla extract, corn syrup, baking soda and salt. Then stir in the melted butter and peanut butter, followed by the oats and flour. Lastly, stir in the chocolate chips, Reese's pieces and M&M's. Let the dough rest for 30 minutes.

3. Drop the dough by ¼ cupfuls onto baking sheets (if weighing, each ball of dough was approximately 2.7 oz or 77g). Use your fingers to flatten the dough slightly. Baking for 10-12 minutes, or until the cookies are a light golden brown. Cool on a rack and then store in an airtight container at room temperature.

*Note: I found that since I used both M&M's and Reese's Pieces, some of the candy pieces fell out when scooping the cookies if a particular ball of dough was overrun with both. Not a big deal, just know that you might lose some candy.

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(Recipe adapted from The King Arthur Flour Cookie Companion)

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