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No flour triple peanut butter monster cookie bars are loaded with peanut butter, peanut butter chips, mini reese’s pieces, and oatmeal! This recipe makes an entire cookie sheet of bars & they freeze perfectly. Perfect for lunchboxes or snacks for the week.
  If you’ve followed this blog or looked through the recipe index, you know that we are obsessed with all things peanut butter & oatmeal. One of our favorites are these (no flour!) Monster Cookie Bars. It was only a matter of time until I made an all Peanut Butter version of our favorite.
These cookie bars are one of THE BEST things I have eaten. The last time I said that was when I posted these Triple Peanut Butter Monster Cookies. You see the peanut butter pattern here….
Maybe we should count how many times I say peanut butter in this post 🙂
These cookie bars have no flour! They are loaded with peanut buttery goodness in three ways: peanut butter, peanut butter chips, and mini reese’s pieces. They also freeze perfectly. I cut the bars into squares (use a pizza cutter, so easy!) and then put a couple into sandwich bags and place in the freezer. They are actually really good straight from the freezer. Or leave them on the counter for a few minutes or warm in the microwave for 10-15 seconds.
If you love monster cookies, oatmeal, and peanut butter then try these cookie bars and also take a look at all these other monster cookie treats!
(no flour!) Monster Cookie Bars, Triple Peanut Butter Monster Cookies, Monster Cookie Dough Cheeseball Dip, or these Oatmeal Chocolate Chip Peanut Butter Bars. Loaded reese’s oatmeal peanut butter cookies. You seriously can’t go wrong with any of these.
Have a great weekend friends. Thanks for stopping by!
(no flour!) Triple Peanut Butter Monster Cookie Bars
Ingredients
- 1/2 cup (1 stick) butter softened
- 1 ½ cups creamy peanut butter
- 1 cup light brown sugar
- 1 cup granulated sugar
- 3 large eggs
- 1 tablespoon vanilla extract
- 1 ½ cups quick oats
- 3 cups old-fashioned oats
- 1 teaspoon baking soda
- 1 bag (9.9 oz) Reese's Pieces
- 1 cup peanut butter chips
Instructions
- Heat oven to 350° F. Prepare a cookie sheet (12" x 18") and spray with cooking spray. Set aside.
- In the bowl of a stand mixer with the paddle attachment (you can also use a mixing bowl + hand mixer) add the butter, peanut butter, brown sugar, and granulated sugar. Beat on medium speed until fluffy and pale in color. This takes 1-2 minutes.* Beat the full 1-2 minutes, or until pale in color, for the best texture of cookie bars.
- Add the eggs and vanilla extract. Mix together.
- Add in the oats and baking soda. Mix until combined.
- Add in the Reese's Pieces and peanut butter chips. Beat on low speed just until combined. * Reserve some of each to spread on top of the bars before baking. This is optional. Just makes them look pretty.
- Dump the dough onto the cookie sheet and spread it out. If the dough is too sticky, try spraying your hands with cooking spray or using a silicone spatula to spread it out. Sprinkle the reserved or extra Reese's Pieces and peanut butter chips on top and gently press down.
- Bake for 17-20 minutes. The edges will be lightly browned and the middle will still look pale and underdone, but it will finish baking as it cools.
- Let cool for at least an hour so the bars can firm up and come together. Cut into squares with a pizza cutter (so easy this way) or a knife.
Notes
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Tried these today and I loved them!! My family did, too. My 11 yr old son said- “These are a 10 out of 10, I could not stop eating them!” I used all quick oats, 3/4 cup of each sugar, chunky peanut butter and chocolate mixed with peanut butter chips. Then I put mini Reese’s cups on top. Just used what I had around ?. These are very versatile and a large recipe. Easy to make, too!! Thank you so much!
I love your variation! My kids can’t stop eating them either 🙂 Thanks so much, Anne, for coming back and commenting and for your kind words!
I know I’m crazy to comment again, but my husband loved these so much he made them yesterday. It was simple for him and they must have been delicious because the whole pan is already gone!
Hey! I love hearing from readers who have tried recipes…… It makes my day, so thank you! I’ll be honest, I make a lot of things but these monster cookie bars are by far, the one thing that we make over and over again. We love them too, and I am so glad you guys love them! Have a good day 🙂
Hi! Do you think it would work to sub. mini Reese’s Cups instead of the Mini Reese’s Pieces ? Cause i’m not really a fan of the Reese’s Pieces…..But I love chopped up Reese’s Peanut Butter Cups in my Oatmeal Chocolate Chip Cookies so I thought they would taste good in these bars
Everything a good cookie should be! Quick to make, it uses everything you already have on hand, delicious soft and chewy.
Thank you so much! What a kind comment 🥰
I was confused by the instructions because it says to put on a cookie sheet, but in looking at the pictures, I’m assuming that was a typo and it should be in a baking pan (with sides not a baking sheet).
Yeah, one of those things that people always have a different name for 😆 but yes, a baking pan with sides is perfect!