Monster Bars (Ready In Less Than 1 Hour)
If you like monster cookies, you’ve got to try monster bars. They’re just as delicious and require less hands-on time. Best part? This recipe is loaded with chocolate chips and M&Ms.
Growing up, I made at least one pan of bars or batch of cookies a week. I’d thumb through the same church cookbook, its pages stained with butter, dusted with flour, and softened from years of enthusiastic baking.
One of my favorite recipes to make was monster cookies. I eventually expanded into monster bars.
A Midwestern Favorite
If you’re not familiar, monster cookies (and monster bars) are a Midwestern favorite. They’re packed with oats, peanut butter, chocolate chips, and M&Ms. Pretty much all of the good stuff.
They’re popular at picnics, church potlucks, and bake sales. Kids love them. Adults love them, too.
If you’re looking to make a pan of bars for an event – or perhaps to bring to a friend or neighbor in need – consider these delicious monster bars.
Why You’ll Love These Monster Cookie Bars
- Makes a generous 9×13 pan
- Tastes like the original monster cookie, but less work
- Uses simple pantry ingredients
- Freezer-friendly
- Perfect for sharing or giving away
- They’re colorful and pretty – kids love them!
Ingredients: What You’ll Need
- Peanut butter: I prefer chunky peanut butter for more texture and flavor, but creamy works just as well. Just be sure to use regular peanut butter – not the natural peanut butter that separates.
- Oats: Old-fashioned oats work best for this recipe. Quick oats will work but result in a softer bar with less texture.
- M&Ms: The best part! I load my monster cookie bars with M&Ms. For the best appearance, place some of the M&Ms on top of the dough before baking.
- Chocolate chips: Semi-sweet balances the sweetness, but milk chocolate works too.
- Honey: Just a squeeze of honey helps keep the bars chewy.
- Eggs
- Butter
- Vanilla
- Brown sugar & white sugar
- Dry ingredients: All-purpose flour, salt, baking soda
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A Recipe To Share With Friends & Family
My favorite part about growing up in small-town Minnesota is how well neighbors and friends cared for each other. This often involved making a meal or dessert and dropping it off at someone’s door. If someone has been sick, if someone has lost a loved one, if someone is going through a hard time… food might just be the thing that helps them get through.
Consider making these peanut butter monster bars for someone who could use a pick-me up.
Tips For Perfect Monster Cookie Bars
- Don’t overbake – they should look slightly soft in the center
- Line the pan with parchment paper for easier removal
- Press reserved M&Ms on top before baking for a prettier appearance
- Let them cool completely before cutting for cleaner squares
- Got extras? Freeze in an airtight container for up to 3 months
Frequently Asked Questions
Can I make monster bars without peanut butter?
Peanut butter is one of the signature ingredients in Monster Bars, adding both flavor and structure to the dough. If you need a peanut-free version, you can experiment with a creamy sunflower seed butter, though the flavor and texture may be slightly different. I haven’t tested this substitution, so I can’t guarantee the results.
Can I use quick oats instead of old-fashioned oats?
Yes, but the texture will be different. Old-fashioned oats give Monster Bars their hearty, chewy texture, while quick oats create a softer, more uniform bar. For the best results, I recommend sticking with old-fashioned oats.
Can I freeze monster bars?
Absolutely! Once the bars have cooled completely, cut them into squares and store them in an airtight container or freezer bag. They’ll keep well in the freezer for up to 3 months. Thaw them at room temperature for about 30 minutes before serving.
Why are my monster bars dry?
Dry monster bars are usually the result of overbaking or measuring too much flour or oats. Bake just until the edges are set and the center no longer looks wet. The bars will continue to firm up as they cool. For the most accurate measurements, spoon the flour into your measuring cup and level it off rather than scooping directly from the bag.
More Favorite Bar Recipes Straight From My Midwestern Kitchen
- Million dollar bars
- Whiskey brownies
- 3 ingredient Nutella brownies
- No-bake peanut butter bars
- Old-fashioned church lady crispy cookies
Monster Cookie Bars
Remember to save some of the M&Ms to top the bars before baking. This will make for a more visually-appealing cookie bar.
Ingredients
- 1/4 cup butter, softened
- 2/3 cup peanut butter (creamy or chunky)
- 1/2 cup white sugar
- 1/2 cup brown sugar
- 2 eggs
- 2 teaspoons honey
- 1 teaspoon vanilla
- 1/4 teaspoon salt
- 1 teaspoon baking soda
- 2 1/4 cups old-fashioned oats
- 1/2 cup + 2 tablespoons all-purpose flour
- 3/4 cup chocolate chips
- 10 ounce bag M&Ms
Instructions
- In a large mixing bowl, cream the butter, peanut butter, sugars, eggs, honey, and vanilla, and beat until smooth and light; about 2 to 3 minutes.
- Mix in salt and baking soda. Fold in oats and flour. Add chocolate chips and 3/4 of the M&Ms.
- Heat oven to 350F. Place in a greased 9x13-inch pan (or line with parchment paper). Place remaining M&Ms on top of bars.
- Bake for 22 to 25 minutes - but watch pan closely as baking times vary from oven to oven. Test by inserting a clean knife into the middle of the pan. These bars are best ever so slightly underbaked - the middle should be set but still soft.