Monster cookie bars with peanut butter and oatmeal –If you’re in the mood for a sweet treat that combines the best of cookies and bars, then these Monster Cookie Bars are just what you need! They’re deliciously chewy, packed with chocolate chips, peanut butter M&Ms, and oats for that perfect cookie texture. Whether you’re baking for a party, a special occasion, or just to satisfy a sweet tooth, these bars are sure to impress. Let’s dive right into the recipe!
Monster Cookie Bars
These decadent bars are a crowd-pleaser! With vibrant colors from the M&Ms and rich flavors from the oats and chocolate chips, you’ll find it hard to just eat one.

Ingredients
- 1 cup creamy peanut butter
- 1/2 cup unsalted butter, softened
- 1 cup brown sugar, packed
- 1/2 cup granulated sugar
- 2 large eggs
- 1 teaspoon vanilla extract
- 1 cup rolled oats
- 1 cup all-purpose flour
- 1 teaspoon baking soda
- 1/2 teaspoon salt
- 1 cup chocolate chips
- 1 cup peanut butter M&Ms
Instructions
- Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking dish or line it with parchment paper for easy removal.
- In a large mixing bowl, combine the creamy peanut butter and softened butter. Beat until smooth and creamy.
- Add the brown sugar and granulated sugar to the butter mixture, and mix until well combined.
- Mix in the eggs, one at a time, followed by the vanilla extract. Beat until smooth.
- In a separate bowl, whisk together the rolled oats, all-purpose flour, baking soda, and salt.
- Gradually add the dry ingredients to the wet ingredients, mixing until just combined. Be careful not to overmix.
- Fold in the chocolate chips and peanut butter M&Ms, ensuring they’re evenly distributed throughout the batter.
- Spread the mixture evenly into the prepared baking dish.
- Bake for about 20-25 minutes, or until the edges are golden and a toothpick inserted in the center comes out with a few moist crumbs.
- Allow the bars to cool in the pan for about 10 minutes before transferring them to a wire rack to cool completely.
- Once cooled, slice them into squares and enjoy your delicious Monster Cookie Bars!
These bars are perfect for any occasion, whether you’re enjoying a cozy night in or celebrating with friends. The combination of flavors and textures makes them irresistible, so be prepared to share—if you can! Enjoy!