Mushy, chewy, and LOADED with goodies, these peanut butter Monster Cookie Bars are made in a single bowl and prepared in below an hour. When youâre a fan of chocolate, peanut butter, and oats, youâre gonna love them!
These bars do comprise flour, however in case you want a gluten-free model, attempt my oatmeal monster cookies.

3 Tasty Cookies in 1 Bar!
When you love oatmeal cookies, peanut butter cookies, and chocolate chip cookies, these bars are for you! They even have some colourful M&Mâs tossed in to make them further enjoyable!
Melted butter makes them good and chewy, and the oats add an excellent texture. And naturally with two sorts of chocolate chips plus the colourful candies, they’re positive to please any chocoholic.

Easy methods to make chewy monster cookie bars:
- PREP â Soften the butter in a massive bowl within the microwave. Spray a 9Ã13â³ pan with cooking spray. Preheat your oven to 350°.
- WET INGREDIENTS â Whisk the brown sugar into the melted butter till no lumps stay. Add the eggs, peanut butter, and vanilla; whisk till clean.
- DRY INGREDIENTS â Add the flour, baking powder, rolled oats, chocolate chips, and M&Mâs. Reserve a number of the chocolate chips and M&Mâs to press on prime of the bars.
- BAKE â Press the monster cookie dough evenly within the backside of the ready baking pan utilizing moist arms. Sprinkle with chocolate chips and M&M candies. Bake at 350° for about 35 minutes, or till barely set within the center.
- COOL â We really get pleasure from these bars ooey gooey and heat, however they’re simpler to chop after they’re fully cool. Itâs as much as you!

Storing leftover monster bars
These bars will final for 4-5 days at room temperature if saved in an hermetic container. For optimum freshness, you may wrap them individually in plastic wrap and they’ll last as long as every week.
It’s also possible to freeze the bars. I like to recommend letting them cool fully, wrapping in plastic wrap, and putting them in heavy-duty freezer baggage. They are going to final within the freezer for 4-5 months. Allow them to thaw at room temperature.
PRO TIPS:
- For greatest outcomes, use common creamy peanut butter like Jif or Skippy. Pure peanut butter doesnât work fairly as effectively.
- If all you could have is crunchy peanut butter, add an extra 1/3 cup or the bars are typically dry.
- Earlier than measuring peanut butter, spray your measuring cup with cooking spray and it’ll slide out a lot simpler!
VARIATIONS:
- For much more peanut butter taste, stir in chopped roasted peanuts, peanut butter chips (my favourite!), or Reeseâs items.
- In case you have leftover leftover halloween sweet bars, you can chop them up and use them rather than the chocolate chips or M&Mâs.
- I make these with quaint oats as a result of thatâs what I’ve available, however fast oats would additionally work.
- Want a giant batch to feed a crowd? You possibly can double the recipe and bake them in a rimmed cookie sheet. Lower the baking time by about 10 minutes.

MONSTER COOKIE BARS RECIPE
Yield: 2 dozen
Peanut Butter Monster Cookie Bars
All the flavour and texture of monster cookies, however in fast and simple bar kind! Swap out the M&M colours to match any vacation.
Prep Time
quarter-hour
Prepare dinner Time
half-hour
Complete Time
45 minutes
Elements
- 1 cup butter, melted and barely cooled
- 2 cups brown sugar
- 2 massive eggs
- 1 cup creamy peanut butter
- 1 Tbsp vanilla extract
- 1 1/2 cups all objective flour
- 1/2 tsp baking powder
- 2 1/2 cups old style oats
- 3/4 cup semi-sweet chocolate chips
- 3/4 cup milk chocolate chips, divided
- 1 1/2 cups M&M’s, divided
Directions
- Soften the butter within the microwave in a big glass bowl; put aside.
- Spray a 9×13″ pan with non-stick cooking spray. (For simpler cleanup, line the pan with parchment paper or foil first.) Preheat your oven to 350 levels.
- Add the brown sugar to the butter and whisk till clean. Whisk within the eggs, peanut butter, and vanilla.
- Stir within the flour, baking powder, oats, semi-sweet chocolate chips, 1/2 cup of the milk chocolate chips, and 1 1/4 cups of the M&M’s.
- Press dough into the ready pan. Sprinkle the remaining 1/4 cup of chips and 1/4 cup M&Ms on prime.
- Bake at 350° for 28-35 minutes or till barely set within the center and golden brown across the edges. For mushy & chewy bars, it is higher to under-bake quite than over baking.
- Let the bars cool for at the least 20 minutes, however they reduce extra cleanly after they’ve cooled for an hour or two.
Notes
-When you use crunchy peanut butter, you have to to make use of an extra 1/3-1/2 cup of peanut butter.
Advisable Merchandise
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Vitamin Data:
Yield:
24
Serving Measurement:
1
Quantity Per Serving:
Energy: 375Complete Fats: 20gSaturated Fats: 10gTrans Fats: 0gUnsaturated Fats: 8gLdl cholesterol: 39mgSodium: 146mgCarbohydrates: 45gFiber: 3gSugar: 30gProtein: 6g
These scrumptious monster cookie bars are all the time an enormous hit at potlucks, picnics, and bake gross sales!
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