These monster cookies are soft, chewy and have classic fillings of oats, M&Ms, and chocolate chips! No chilling time is required and you can enjoy a fresh batch in under 30 minutes! 😋
Looking for more tasty peanut butter treats? Try our friend's Microwave Peanut Brittle over at Cook Like A Master!
What Kind of Peanut Butter to Use
Use peanut butter that doesn't have a layer of oil on top. The extra wetness from the oil can cause the cookies to spread in the oven. You want to use a peanut butter that's creamy, thick and is no-stir.
- Dry Ingredients: all-purpose flour, baking soda, baking powder and salt
- Unsalted Butter: let the butter come to room temperature so it can easily cream with the sugars
- Sugars: This recipe uses a mix of both brown and white sugar. Using more brown sugar than white adds a little chewiness to the cookies.
- Creamy Peanut Butter
- Vanilla Extract
- Add In's: This recipe uses a classic mix of old-fashioned rolled oats, M&Ms and chocolate chips.
Please see the full list of ingredients and measurements at the bottom of the post.
Variations & Substitutions
One of the fun things about Monster cookies is how versatile they are!
Try different variations by adding chopped nuts, like pecans or walnuts, and switching out for a different flavor of chocolate chip.
You can easily decorate them to match any occasion. Use M&Ms in seasonal colors or add some sprinkles - check out how we made them spooky in our Halloween Monster Eye Cookie version! 🎃🧟♀️
You can keep these cookies at room temperature for about a week as long as they're stored in a sealed container.
One of the great things about these cookies is that you can freeze them! Keep them in a sealed, freezer-safe bag for up to three months. When you want to serve them, let them thaw on the counter at room temperature.
- 1 cup all-purpose flour
- ¼ teaspoon baking soda
- 1 teaspoon baking powder
- ¼ teaspoon salt
- ½ cup unsalted butter room temperature
- ¾ brown sugar
- ¼ cup white sugar
- ½ cup creamy peanut butter
- 2 large eggs room temperature
- 1 teaspoon vanilla extract
- 1 ¼ cup old-fashioned rolled oats
- ¾ cups M&Ms
- ¾ cup semi-sweet chocolate chips
- Preheat the oven to 350℉ and line two baking sheets with parchment paper.
- Whisk together the flour, baking soda, baking powder and salt in a small mixing bowl.
- Cream the butter and sugars together in a large mixing bowl. Start on a low speed for about 30 seconds, until the butter and sugar begin to clump together, so it doesn’t fly out of the bowl. Then increase to a medium-high speed for about 1 ½ minutes.
- Then, mix in the peanut butter on a low speed. Mix until just combined.
- Add the eggs and vanilla extract mix again on low speed.
- Scrape down the sides and add in the dry ingredients. Mix again until just combined.
- Use a rubber spatula to fold in the oats, M&Ms and chocolate chips to the dough. Optional, keep some extra fillings to top the balls of cookie dough with.
- Scoop 1 tablespoon-size balls of cookie dough and place them on the baking sheets about two inches apart. Top with the extra fillings if reserved.
- Bake each sheet, one at a time, on the middle rack of your oven for 12-13 minutes, until the edges of the bottom edges of the cookies begins to turn a golden color. Remove them from oven and let the cookies continue to sit and bake on on the tray for another five minutes. Then, transfer the cookies to a cooling rack.
- Using room temperature ingredients will allow them to mix faster and more easily
- The oven will be warmer the longer it's on, so the second tray of cookies may bake slightly faster. Check on it about one minute earlier than the first one.
- The cookies continue to bake as they sit on the hot baking tray when you remove them from the oven. Don't skip the extra five minutes they need sitting on it before moving them to a wire rack.
- Use two separate baking sheets for each round of cookies, or allow the first baking sheet to cool to room temperature before placing the second batch of cookies on it. If you place the cookie dough on a warm baking sheet, it can cause the cookies to spread.
Please note, Holiday Sweets N Treats isn't a professional nutritionist. Any and all nutritional information shared is an estimate. If you're following a specific diet or counting calories, we suggest you use the nutrition calculator of your choice. Calories can vary depending on the brands and products used.