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These Giant Monster Cookies are the best you’ll ever try! Huge, chewy, and soft-baked, they are fully loaded with peanut butter cups, candies, and chocolate chips – and adding candy eyes brings a spooky element to your Halloween treats!
So, in all the hustle and bustle of my very travel-heavy vacation last week (you might have seen some of it on my Instagram stories), I absolutely flubbed on the recipe I planned to share for Halloween.
In place of that equally yummy Chocolate Rum Pumpkin Monkey Bread was supposed to be this fully-loaded Giant Peanut Butter Monster Cookie recipe.
The colors were perfect.
The flavors were perfect (hello, leftover trick-or-treat candy!!)
There’s even a shot in this post with a few cookies that I stuck spooky candy eyes in for fun.
Lucky for us, it’s not too late to enjoy these. After all, it’s still fall (arguably) and – above all – there is no out-of-season for peanut butter lovers!
JUST TAKE ME TO THE MONSTER COOKIES ALREADY!
If you’d rather skip my (pretty darn helpful) tips and tricks, essential cooking info, and similar recipe ideas – and get straight to this deliciously easy monster cookie recipe, just scroll right on down to the bottom of the page where you can find the printable recipe card!
These cookies are for the folks out there that adore peanut butter and chocolate together…but are bigger on peanut butter.
Classic Monster Cookies, a mash-up of oatmeal and peanut butter cookies, are jammed full of chocolate chips and M&Ms.
Now I will say I’ve never met an M&M I didn’t like, but I’m a real sucker for Reese’s Pieces.
For fun, these Peanut Butter Monster Cookies leave out much of the chocolate.
But they’re still SO GOOD!
I swapped M&Ms for those beloved candy coated peanut butter bits. The amount of chocolate chips are reduced in favor of mini peanut butter cups.
I even considered tossing some peanuts in there, and when I saw how big they were after they were baked – honestly, it’s still an option.
Try it out and tell me they’re as amazing as I think they’ll be with that extra crunch!
How To Make Monster Cookies:
- First, line a few baking sheets with silicone mats or parchment paper.
- Next, add sugars, peanut butter, and melted butter in an extra large bowl. Mix it well until it’s combined and fluffy, then add the eggs and vanilla.
- In another bowl, stir together the oats, flour, baking soda, salt, and baking powder. Add it to the peanut butter mixture and stir until it’s just combined.
- Then, fold in the Reese’s Pieces, peanut butter cups, and chocolate chips (and peanuts if you want!)
- Now, cover the bowl and allow the batter to rest for at least an hour.
- When you’re ready to bake, preheat your oven to 350 degrees F.
- Measure out 13 1/4-cup potions and place them on the baking sheets. You should place no more than 4 on each sheet to allow enough room for them to spread. Lightly press them down to flatten them a bit, then feel free to add more candies to the top if you want.
- Finally, bake for 15-18 minutes, to your desired softness/crispiness. Cool for 5 minutes, then transfer them to a cooling rack.
Tips For Perfect Monster Cookies:
- For the best texture, my friend Amanda suggests leaving oatmeal cookie dough out to allow the oats to absorb the liquids in the fats. The hour-long wait in this recipe isn’t necessary, but having tested the theory, I recommend it!
- For the best flavor, toast the oats! I’ve made these cookies three times, and (as with nuts) the second batch with the toasted oats was far superior. Toast the oats at 350 degrees for 10-12 minutes, then cool completely before folding them into the batter.
- For even more texture, use crunchy peanut butter, or add peanuts to the batter! Lightly salted would add a great taste to these. Of course, if you’d prefer you can always just use more Reese’s candies!
- For smaller cookies, use a small cookie scoop and reduce bake time by 3 minutes.
- For larger cookies, make 6-7 balls of dough using 1/2-cup measure. Press them down after 10 minutes, then bake an additional 8 (a total of 18 minutes).
- To make these babies gluten free, leave out the flour and baking powder. Use 4 cups of gluten-free oats, and increase the baking soda to 2 teaspoons.
- Hate chocolate? Use peanut butter chips or toffee bits!
LOOKING FOR MORE COOKIE RECIPES?
- Bakery Style Triple Chocolate Chip Cookies
- Chocolate Chip Cookie “Bronados”
- Oatmeal Peanut Butter Pretzel Chunk Cookies
- Pumpkin Butterscotch Streusel Cookies
HELPFUL KITCHEN TOOLS FOR MAKING MONSTER COOKIES:
See – spookayyyyyy!
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Giant Peanut Butter Monster Cookies
- 1 cup packed light brown sugar
- 1 cup granulated sugar
- 1 cup creamy peanut butter
- 1 stick butter softened
- 3 eggs room temperature
- 1 teaspoon vanilla extract
- 2 ¼ cups oats
- 1 cup all-purpose flour
- 1 teaspoon baking soda
- ½ teaspoon salt
- ¼ teaspoon baking powder
- 1 cup Reese’s Pieces
- ½ cup mini peanut butter cups
- 1 cup chocolate chips
- Eyeball sprinkles optional
- Preheat the oven to 350 degrees F. Line cookie sheets with parchment paper or nonstick baking mats.
- In a very large mixing bowl, combine the sugars, peanut butter, and butter. Mix well. Add the eggs one at a time and beat well between additions. Add vanilla. Mix well.
- Combine oats, flour, baking soda, salt, and baking powder in a medium bowl and whisk well. Add to wet ingredients and mix until combined. Fold in the Reese’s Pieces, mini cups, and chocolate chips.
- Cover and allow batter to rest for 45-60 minutes at room temperature.
- Measure out ¼ cup-sized portions and place them on the prepared cookie sheets, no more than 4 to a sheet. Flatten the cookies with your palm a bit, and press additional candies and sprinkles into cookies, if desired.
- Bake for 15-18 minutes, until the edges are lightly golden brown. Do not overbake. Remove from oven and allow to cool 5 minutes before transferring to wire racks. When cool, store in large resealable plastic bags.