Who doesn’t love a cookie bar packed with peanut butter, chocolate chips, and M&M’s? If you’re a fan of chewy, gooey desserts, this Monster Cookie Bars recipe will quickly become your favorite go-to treat. With just a few pantry staples, you can whip up a batch of these colorful, crowd-pleasing bars that are perfect for any occasion.
Imagine biting into a soft, buttery cookie that’s loaded with your favorite mix-ins, all baked together in one convenient pan. Whether you’re hosting a party or looking for a fun treat to make with the kids, these bars deliver on flavor, fun, and ease. Plus, they’re so versatile you can customize them for any event or holiday.
Ready to make a dessert that’s guaranteed to impress? Keep reading to find out how you can create these irresistible Monster Cookie Bars, and get ready to wow your family and friends with your baking skills!
What Are Monster Cookie Bars?
Monster Cookie Bars are a spin on the classic monster cookie, which traditionally combines peanut butter, oats, and chocolate chips. By transforming them into bar form, we make the process even easier—no need to scoop individual cookies. These bars are thick, soft, and loaded with all your favorite mix-ins like chocolate chips and M&Ms.
What sets Monster Cookie Bars apart is their balance of flavors: the nuttiness of peanut butter, the chewy texture of oats, and the sweetness of chocolate all come together in one satisfying bite. They’re a fun and colorful dessert that appeals to kids and adults alike.
Why You’ll Love This Recipe
There are so many reasons to love these Monster Cookie Bars:
- No need to roll individual cookies – Simply press the dough into a pan and bake!
- Great for parties and gatherings – Easy to slice and serve, perfect for sharing.
- Customizable – Switch up the mix-ins for any occasion (think holiday-themed M&Ms).
- Freezer-friendly – You can make them ahead and store them for later.
Ingredients You’ll Need
To make these chewy, flavorful cookie bars, you only need a few pantry staples. Here’s what you’ll need:
Dry Ingredients
- 2 cups all-purpose flour
(Tip: To make these gluten-free, use a 1-to-1 gluten-free flour blend like Cup4Cup.) - 2 cups old-fashioned oats
(Ensure they’re certified gluten-free if necessary.) - 1 teaspoon baking soda
(For lift and lightness in the bars.) - 1 teaspoon sea salt
(A touch of salt enhances sweetness and balances flavors.)
Wet Ingredients
- 1 cup unsalted butter, at room temperature
(Softened butter helps create a soft, chewy texture.) - 1 cup creamy peanut butter
(Avoid natural peanut butter; use a brand like Jif or Skippy for consistency.) - 1 ½ cups packed light brown sugar
(The molasses in brown sugar adds moisture and a rich flavor.) - ½ cup granulated sugar
(Adds sweetness and structure.) - 2 large eggs
(Eggs bind the ingredients and add richness.) - 1 tablespoon vanilla extract
(Don’t skimp on the vanilla—it adds depth of flavor.)
Mix-ins
- 1 ¼ cups semi-sweet chocolate chips
(Feel free to use milk or dark chocolate if you prefer.) - 1 ½ cups M&Ms, divided
(You can swap these for different-colored M&Ms based on the season.)
How to Make Monster Cookie Bars
The process for making these bars couldn’t be simpler. Here’s how to do it, step-by-step.
Step 1: Preheat and Prepare the Pan
Preheat your oven to 350°F (175°C). Grease a 9×13-inch pan with non-stick cooking spray, or line it with parchment paper for easy removal.
Step 2: Mix the Dry Ingredients
In a large mixing bowl, whisk together the flour, oats, baking soda, and salt. Set aside.
Step 3: Cream the Wet Ingredients
In the bowl of a stand mixer, cream together the butter, peanut butter, and both sugars (brown and granulated) until smooth. This should take about 2-3 minutes on medium speed.
Step 4: Add Eggs and Vanilla
Once the butter mixture is smooth, add in the eggs one at a time, followed by the vanilla extract. Continue mixing until fully combined.
Step 5: Combine Wet and Dry Ingredients
Slowly add the dry ingredients to the wet ingredients, mixing until just combined. Avoid over-mixing, as this can make the bars too dense.
Step 6: Fold in Chocolate Chips and M&Ms
Stir in the chocolate chips and 1 cup of M&Ms using a spatula. The dough will be thick and chunky, perfect for spreading in the pan.
Step 7: Spread the Dough in the Pan
Press the dough evenly into the prepared pan using a spatula or your hands. Sprinkle the remaining ½ cup of M&Ms on top.
Step 8: Bake and Cool
Bake the bars for 25-35 minutes, or until they’re golden brown around the edges and set in the center. Be careful not to over-bake them; you want them to stay soft and chewy.
Once baked, remove the pan from the oven and sprinkle with a bit of flaky sea salt for extra flavor. Let the bars cool completely in the pan before slicing them into squares.
Storage Tips
Room Temperature
Store your baked Monster Cookie Bars in an airtight container at room temperature for up to 4 days. This will keep them soft and chewy.
Freezing
You can also freeze the baked bars for up to 3 months. Wrap each bar individually in plastic wrap and store them in a freezer-safe bag or container. To thaw, simply leave them at room temperature for a few hours, or pop them in the microwave for a quick warm-up.
Make-Ahead Option
The dough can be made ahead of time and stored in the refrigerator for up to 48 hours before baking. This is especially convenient if you’re prepping for a big event or just want to save time.
Variations and Substitutions
One of the best things about Monster Cookie Bars is their versatility. Here are a few fun variations you can try:
- Holiday-Themed Bars: Use colored M&Ms for different holidays—red and green for Christmas, pastel for Easter, or orange and black for Halloween.
- Nut-Free Option: Substitute sunflower seed butter for peanut butter to make these bars nut-free.
- Add More Mix-ins: Get creative by adding other fun ingredients like chopped nuts, dried fruit, or even crushed pretzels for a salty-sweet combo.
- Gluten-Free Version: Use gluten-free oats and a gluten-free all-purpose flour blend to make this recipe suitable for those with gluten sensitivities.
Common Questions About Monster Cookie Bars
Can I Use Natural Peanut Butter?
While natural peanut butter may seem like a healthier option, it’s not recommended for this recipe. The oils in natural peanut butter can separate, leading to a drier, crumbly texture in your bars. Stick with creamy, processed peanut butter for the best results.
How Do I Know When the Bars Are Done?
The edges of the bars should be lightly golden, and the center should be set but still soft. The bars will continue to firm up as they cool, so don’t worry if they seem a little underdone when you first take them out of the oven.
Can I Add Protein Powder to These Bars?
Yes! To make these bars more protein-packed, you can replace a small portion of the flour with protein powder. Just be sure not to add too much, or it could affect the texture.
Why Trust This Recipe?
At My Kitchen Talk, we pride ourselves on providing clear, accurate, and trustworthy recipes. Each recipe is tested thoroughly to ensure that it’s not only delicious but also easy to follow. Whether you’re a novice baker or a seasoned pro, you can rely on this Monster Cookie Bars recipe to deliver soft, chewy, and flavorful results every time.
Conclusion
Monster Cookie Bars are a fun, easy-to-make dessert that’s perfect for any occasion. With a mix of chewy oats, creamy peanut butter, and chocolatey goodness, these bars are sure to be a hit with both kids and adults alike. Whether you’re whipping them up for a party or just for a treat at home, these bars are guaranteed to impress.
Happy baking, and don’t forget to share these delicious bars with friends and family!