These Flourless Monster Cookies are made entirely with oats - no flour at all - and are packed with peanut butter and chocolate. Chewy middles, crisp edges, and they're fantastically freezer friendly.
Flourless Monster Cookies - at a Glance
- ⏱ Prep Time: 25 minutes
- 🔥 Cook Time: 12 minutes
- ⌛ Total Time: 37 minutes
- 👪 Serves: 60
- 🍽️ Calories: 141
- 🍫 Main Ingredients: Peanut butter, butter, granulated and brown sugars, eggs, oats, chocolate chips, M&Ms.
- 👌 Why You'll Love It: Chewy-crisp monster cookies made with rolled oats and no flour.
SUMMARIZE & SAVE THIS RECIPE ON
I've made monster cookies since my daughter started grade school, but it took me a couple of years before I found the perfect recipe for them. It was in the house all along - I wrote it in a hand-written recipe notebook from 2003, despite never having tried them. My husband Alex pulled it out while I was out of town to try it, and we decided it's definitely a keeper!
No clue where I found this recipe originally before writing it out, but I'll never try a different one. I love cookies like this where you don't need flour - and when I bring them to people, I love telling them what's not in them. And since it makes 60 cookies, I share them with others often - it's no sacrifice to spare a few.
If you like whole grains in treats, you'll also enjoy my Chocolate Chip Cookie Scones, Whole Wheat Zucchini Bread, and my Chocolate Peanut Butter Bites.
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Why You'll Love These Cookies
- 🍫 Loaded with lots of peanut butter and chocolate in every bite.
- ⏳ Corn syrup keeps the cookies soft for days.
- 🍪 An irresistible texture with chewy middles and crisp edges.
- 🎉 A large batch - makes 60 cookies to feed a crowd.
- 🧊 Perfect to make ahead - make some now and freeze the rest of the dough for later.
Key Ingredients
Peanut butter: Use regular, creamy, store brand peanut butter. "Natural" peanut butter without additional oil or sugar will not work properly. Crunchy peanut butter may work, but your batter may end up a bit dry. The amount of peanut butter here binds the dough together in a way that flour usually does.
Rolled oats: Both old-fashioned and quick-cooking oats work; we don't notice much difference between the two in cookies. Don't use instant oats (too mushy) or steel-cut oats (too thick and won't cook properly). Adding oats gives these cookies a toothsome texture that a lot of gluten-free cookies lack.
Chocolate chips and M&Ms: Store-brand semisweet chips work great. M&Ms are milk chocolate and add contrast; any candy-coated chocolate pieces should work.
Corn syrup: Optional, but I recommend it. Corn syrup keeps the cookies soft and chewy on Days 2, 3, and beyond. Cookies without corn syrup feel a bit stale by Day 3 and don't have as chewy a texture. I use light corn syrup, but dark should be okay; agave or honey should also work, but may slightly change the cookies' flavor. Corn syrup works the same in my Gooey Butter Cake, keeping the gooey layer softer for longer.
How to Make Flourless Monster Cookies
Use a stand or electric hand mixer for this recipe. It makes a ton of cookie dough, and it's hard to beat together the butter and peanut butter by hand.
One: Cream the butter, peanut butter, brown sugar, sugar, and corn syrup. Mix on medium speed for 1-2 minutes, until creamy and lightened.
Two: Scrape the bottom. Add the eggs and vanilla. Mix on low 30 seconds to break them up as they slosh around. Scrape up the bottom, then mix for another 30-60 seconds on medium.
Three: Scrape up the bottom. Add the oats, and sprinkle the baking soda over them so it doesn't clump up. Stir on low just until mixed.
If using a handheld mixer, switch to a rubber spatula to mix.
Four: Add the chocolate chips and M&Ms. Stir on low just to combine.
With oats and no flour, you can't really overmix the dough. Using low speed is just because the dough is thick and the bowl is full.
Five: Use a medium (1.5-tablespoon or #40) cookie scoop, or two spoons, to scoop dough. Place cookies 2 inches apart on a parchment- or silicone mat-lined baking sheet.
Six: Bake for 10-12 minutes, until the cookies are set and look slightly dried. They'll be puffy, and perhaps slightly browned.
In my oven, 10 minute cookies are a little underdone. 12 minute cookies are a bit less chewy, although they're still not crunchy. 11 minutes is perfect for me; your baking times will vary based on your oven.
Let the cookies cool for 5-10 minutes before removing them from the baking sheet. They'll deflate a little as they cool; this is normal.
Serving and Storage
Store cookies in an air-tight container at room temperature. Cookies are best on the day they're made, and they're still pretty good on the day after. If you've added corn syrup, they'll still be pretty chewy by Day 3. (I've never had any leftover after that!)
There's no wrong way to serve monster cookies - they're a hearty snack at any time of day, especially alongside a cold glass of milk.
Make Ahead
Since this recipe makes enough dough for 60 cookies, I usually bake one or two trays and save the rest of the cookie dough for another day, as I do with Sprinkle Cookies and Double Chocolate Caramel Chip Cookies. The dough freezes well, and then you have cookies whenever you want!
Line a plate or a baking sheet with waxed paper or plastic wrap; this helps you pry the frozen balls of dough off later.
Scoop cookie dough onto the lined sheet, crowding the balls of dough as close as you can without them actually touching. Place the tray in the freezer, and leave them there until frozen.
Label a freezer bag with the date and baking instructions. Then pry the dough from the sheet and place them in the bag, squeezing out as much air as possible. (I often forget to put them in a freezer bag for a few days!)
Whenever you want cookies, just heat your oven to 350F. Don't thaw the cookies first - just put them on the baking sheet and bake them from frozen! Bake them for an extra 2 minutes - so, 12-14 minutes.
Monster Cookie FAQs
No - these monster cookies contain only oats, and no flour of any kind, which makes them 100% whole grain.
Oats are naturally gluten-free, but are cross-contaminated since they are usually processed on the same equipment as flour. If you need to avoid gluten, choose oats that are certified gluten-free.
There's two types of "natural" peanut butter. One is peanut butter made from just peanuts, without additional oil or sugar. It does not work in baking unless you make adjustments to the sugar and fat in the recipe.
The other kind of "natural" peanut butter is conventional peanut butter made with sugar and oil, except that it uses palm oil. This kind should work in the recipe since it has additional fat and sugar. However, I dislike it for two reasons. First, the palm oil industry is a major contributor to deforestation, etc., since it largely doesn't use sustainable farming techniques. Second, as a user, I find that the oil separates and I have to stir it back into the rest of the peanut butter.
I personally prefer average-sized cookies, because I can eat more of them than I can giant cookies. To make giant or "monster" monster cookies, use a ¼ cup to measure the dough. Bake for a few minutes extra, until the tops look dried and set.
I accidentally used baking powder the last time I made monster cookies. They turned out fine, but it wasn't ideal. Baking soda reacts with the acid in the brown sugar and helps the cookies spread. The cookies didn't spread properly, so I had to flatten later batches before baking.
More Peanut Butter and Chocolate Treats
I hope this becomes a recipe you'll return to. If you try it, a star rating below helps others find it - and I'd love to hear how yours turns out in the comments! 💕 Questions or trouble? Drop a note, and I'll do my best to help.
📖 Recipe
Flourless Monster Cookies
Equipment
- electric mixer
- medium (#40) cookie scoop
- silicone mats or parchment paper
Ingredients
- 8 tablespoons butter (113 grams; softened)
- 1 ½ cups peanut butter (384 grams)
- 1 ¼ cup brown sugar (250 grams)
- 1 cup granulated sugar (200 grams)
- 1 ½ teaspoon corn syrup (10 grams; optional but recommended)
- 3 eggs (~150 grams)
- 1 ½ teaspoon vanilla extract (7 grams)
- 4 ½ cups rolled oats (360 grams; old-fashioned or quick are both fine)
- 2 teaspoons baking soda
- 1 cup chocolate chips (170 grams/6 ounces)
- 1 cup M&Ms (212 grams/7.5 ounces)
Instructions
- With a stand mixer or hand mixer (affiliate link), combine butter, peanut butter, sugars, and corn syrup. Mix at medium speed for 1-2 minutes, until mixture has lightened in color.
- Scrape the bottom, and then add vanilla and eggs. Mix again on medium speed for about 1 minute, until everything is combined. Scrape the bottom again to look for unmixed bits.
- Add in the oats and the baking soda. (Switch to a rubber spatula if you were using a hand mixer (affiliate link).) Stir on low until everything is mixed in, pausing to scrape the bottom as you go.
- Add the chocolate chips and M&Ms. Stir on low just to combine.
- Using a medium, 1 ½ tablespoon (or #40) cookie scoop, or two spoons, portion dough onto parchment or silicone-lined baking sheets, leaving 2 inches between cookies.
- Bake at 350F for 10-12 minutes. (11 is perfect in my oven, but yours may be different.) The tops will look set and dry, and they will be slightly browned and a little puffy on top, though they will deflate as they cool.
- Cool for 5-10 minutes before removing from the baking sheets.
Freezer Instructions/Make-Ahead
- Scoop the cookie dough onto plates or cookie sheets lined with waxed paper or plastic wrap. Crowd them on as closely as possible, without letting them touch.
- Freeze dough until solid. Remove the balls of cookie dough and store them in a labeled freezer bag.
- To bake, heat your oven to 350F. Place balls of cookie dough 2 inches apart on your parchment-lined sheets. Bake, from frozen, for 12-14 minutes.
Leona Konkel says
This recipe is one of our family favorites. I love that it makes so many, because I restock my stash of freezer cookie dough every time I make it. I hope you love it too. Let me know how it turns out!