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With or without ice cream and hot fudge, these Monster Cookie Bars are sure to be a hit! Peanut butter, M&Ms, oatmeal…they’re the trifecta of perfect cookie bar. These are better than pioneer woman and taste of home combined!
What are Monster Cookie Bars?
Have you ever had a monster cookie? It’s a peanut butter oatmeal cookie that’s filled with chocolate chips and M&Ms. I love them, because they’re a combination of two of my favorite cookie recipes. But as much as I like cookies, I think I like cookie bars better because there is no scooping. I just press the dough in the pan and bake it, easy peasy.
This recipe starts with my favorite peanut butter cookie recipe. I adapted it to add oats to make it MONSTER. And, of course, I added chocolate chips, regular M&Ms, and PEANUT BUTTER M&M’s. I swear, peanut butter M&M’s are my downfall. I can easily eat a 1 lb. bag all by myself!
Once you bake them they become a soft and gooey cookie bar that’s perfect for when you’re craving peanut butter and oatmeal cookies together.
Ingredients Needed
- Butter: As always, I start with unsalted butter that’s been softened. Learn to soften butter quickly!
- Peanut Butter: A must for monster cookies! You can use creamy or crunchy, but use a no-stir brand.
- Sugar: Both granulated and brown sugar makes a soft and chewy bar.
- Flour: I always use all-purpose flour, be sure to measure it correctly.
- Quick Cooking Oats: I prefer baking with quick oats. To make these bars with old fashioned oats you just need to pulse the oats in a food processor to break them down – learn to make your own quick oats!
- Mix-Ins: Chocolate Chips and M&Ms
How to make Monster Cookie Bars
- Beat butter and peanut butter with a hand or a stand mixer until smooth. Mix in both sugars until creamy.
- Add eggs, vanilla, baking soda, and salt and mix until smooth.
- Slowly mix in the flour and oats. Stir in the chocolate chips and M&Ms.
- Press cookie dough into the prepared pan. If desired, sprinkle more M&Ms on top for decoration. Bake for 22-25 minutes in an oven preheated to 350°F.
Monster Cookie Bars FAQ
Bake these 22-25 minutes or until they just lose their glossy sheen.
Store these in an airtight container. Freeze for up to 3 months.
It’s not an exact swap so I suggest making gluten free monster cookies instead.
Monster Cookie Bars
Ingredients
- ½ cup (113 g) unsalted butter softened
- 1 cup (268 g) peanut butter
- ¾ cup (150g) packed brown sugar
- ½ cup (100g) granulated sugar
- 2 large eggs
- 1 teaspoon vanilla extract
- ½ teaspoon baking soda
- ½ teaspoon salt
- ¾ cup (93g) all-purpose flour
- 3 cups (240g) quick cooking oats
- 1 cup (170g) chocolate chips
- 2 cups M&Ms any kind, I used regular and peanut butter
Instructions
- Preheat oven to 350°F. Line a 9×13” pan with foil and spray with nonstick cooking spray.
- Beat butter and peanut butter with a hand or a stand mixer until smooth. Mix in both sugars until creamy. Add eggs, vanilla, baking soda, and salt and mix until smooth, then slowly mix in the flour and oats. Stir in the chocolate chips and M&Ms.
- Press cookie dough into the prepared pan. If desired, sprinkle more M&Ms on top for decoration. Bake for 22-25 minutes or just until the edges are golden brown. Cool before cutting into bars.
- These are great served as bars or as an ice cream sundae! Store in an airtight container for up to 3 days or freeze for up to one month.
Recipe Video
Recipe Notes
- Make Christmas Monster Cookie Bars with holiday M&Ms
- Reese’s Pieces Monster Cookie Bars would be fantastic – just swap the M&Ms for Reese’s Pieces!
- Do not over bake these – they’re best a little under baked and gooey
- How to serve Monster Bars: I love serving these plain, just as a bar cookie, or topping with ice cream!
I love these bars! Pressing in a pan is so much better than scooping. And your take on parenting gives me some hope for the future. I was my mom’s oldest of 3 girls and I’m pretty sure I was her guinea pig for seeing what worked and what didn’t. She was always pretty laid back and we never got kidnapped 🙂
LOL, that’s how my husband feels except the opposite – he was the baby and by the time they got to him they weren’t as worried!
Oh my gosh do these bars look good. Because monster cookies are the bomb in the first place. But in bar form?! Mmm. I think they’d satisfy even my hyperactive sweet tooth!
Always!!
The things you worry about…ok my friend, you just need more wine and you won’t worry as much 🙂 I worry and all of parenting feels like blind stabs in the dark some days, but we’re all just doing the best we can do and you’re an amazing mama! With great looking cookie bars that I want!
Blind stabs in the dark – yes that. Totally!!
I totally agree that cookie bars are way easier than parenting, even though I’m not a parent lol. So let’s just stuff our faces with these, right? I love the flavor of these gorgeous bars, Dorothy! Delish!
Parenting has no answers, which means that we spend all our time trying to avoid sending our kids to endless therapy as adults. I have no idea what to do pretty much most of the time, and I also wake up and think about things and can’t sleep. You are not alone!
And cookie bars? Much easier. And these are heaven. That ice cream on top is such a good idea!!
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