Big Giant Monster Cookies

For cookie lovers craving oversized, bakery-style treats with crisp edges and irresistibly chewy centers.
Loaded with creamy peanut butter, hearty oats, chocolate chips, and colorful M&M candies in every bite.
A fun, family-favorite monster cookie that’s easy to make and impossible to resist!

Quick Answer

Big Giant Monster Cookies are flourless peanut butter oat cookies loaded with chocolate chips and M&Ms. No flour needed, just a hearty oat base that bakes into thick, chewy, bakery-sized cookies.

What Are Big Giant Monster Cookies?

Monster cookies are flourless, peanut butter based cookies built on a flourless peanut butter base of old-fashioned rolled oats instead of wheat flour.

The dough gets loaded with heavy mix-ins like chocolate chips and M&M candies, then scooped extra large so every cookie bakes up thick, chewy, and bursting with texture.

They earned the name from their oversized, colorful, anything-but-plain appearance, a true kitchen-sink cookie built for big appetites.

Why You’ll Love These Giant Monster Cookies

This recipe delivers everything a great cookie should, with zero flour to measure and zero guesswork.

• No flour means no risk of a tough, overworked dough.
• Old-fashioned rolled oats give real chew and structure.
• Loaded with heavy mix-ins for a cookie that’s never boring.
• Naturally gluten-free with the right oats.
• Bakes into thick chewy centers with crisp, golden edges.

Ingredients You’ll Need

This recipe uses eight core components, each playing a specific role in flavor and texture.

Peanut Butter

Creamy peanut butter forms the flourless base of the dough, adding richness, structure, and that signature nutty flavor.

Old-Fashioned Rolled Oats

Rolled oats replace flour entirely, giving the cookies their hearty chew and substantial, bakery-style bite.

Chocolate Chips and M&M Candies

This classic combo delivers melty pockets of chocolate alongside the crunchy, colorful pop of candy shells.

Other Key Ingredients

• Unsalted butter for richness and spread control.
• Granulated and brown sugar for sweetness and moisture.
• Eggs to bind the dough and add lift.
• Baking soda for the right amount of rise.
• Vanilla extract and a pinch of salt to round out flavor.

The Culinary Calculus: Why Monster Cookies Stay Chewy

Rolled oats absorb moisture slowly and hold their shape under heat, unlike flour, which develops gluten and can toughen a dough. Combined with peanut butter’s natural fat content, the oats create a dense, chewy matrix instead of a light, airy crumb. Brown sugar’s molecular structure holds onto extra moisture too, which is exactly why swapping in more granulated sugar dries these cookies out.

How to Make Big Giant Monster Cookies

Making monster cookies comes down to five stages: mix, load, shape, bake, and cool.

1. Prepare the Cookie Dough

Cream the butter, peanut butter, and both sugars until smooth. Beat in the eggs and vanilla until fully combined.

2. Add the Oats and Chocolate Candies

Mix in the baking soda and salt, then fold in the oats, chocolate chips, and M&Ms until evenly distributed.

3. Shape the Giant Monster Cookies

Scoop generous 1/3 cup mounds of dough onto a lined baking sheet, spacing them well apart to allow for spread.

4. Bake the Cookies

Bake at 350°F for 11 to 13 minutes, until the edges look set but the centers are still soft and slightly underdone.

5. Cool Before Serving

Let the cookies rest on the baking sheet for 10 minutes before moving them to a wire rack to finish cooling.

How to Keep Monster Cookies Thick and Chewy

Thick, chewy monster cookies come down to three controllable factors: chilled dough, correct oat measurement, and slight underbaking.

• Chill the shaped dough for 20 to 30 minutes before baking to limit spread.
• Spoon and level the oats rather than scooping straight from the container.
• Pull the cookies while the centers still look slightly underdone.

If you’ve ever wondered why one cookie turns out thick and chewy while another bakes up soft and cakey, our Ultimate Science of Baking takes you behind the scenes. It explains how flour, fat, sugar, moisture, and mixing work together to create the textures you love.

Best Peanut Butter for Monster Cookies

Standard creamy commercial peanut butter, like Jif or Skippy, is the best choice for consistent monster cookies.

• Commercial peanut butter has stabilizers that keep the oil from separating.
• Natural peanut butter can make the dough greasy and spread too much.
• Crunchy peanut butter works too, if you enjoy extra texture.

How to Shape Giant Monster Cookies

Use a 1/3 cup scoop or measuring cup to portion the dough for true bakery-sized monster cookies.

• Roll each portion gently into a ball without compacting it too tightly.
• Press a few extra M&Ms on top before baking for that classic bakery look.
• Space cookies at least 3 inches apart, since they spread significantly.

Monster Cookie Variations

Four simple swaps let you customize the classic monster cookie in new directions.

Chocolate Monster Cookies

Add 1/2 cup of cocoa powder to the dough for a rich, chocolate forward base.

Double Chocolate Monster Cookies

Combine cocoa powder in the dough with both chocolate chips and chunks for maximum chocolate intensity.

Peanut Butter Monster Cookies

Swap the M&Ms for peanut butter chips and add chopped peanuts for an all peanut butter experience.

Candy Monster Cookies

Mix in pretzel pieces, mini candy bars, or seasonal M&M colors for a fully loaded, kitchen-sink version.

Want that same bakery-style thickness with a different flour approach? Our Thick Chocolate Chip Cookies shows how swapping the flour blend can change everything from spread to tenderness.

Common Monster Cookie Mistakes

Most monster cookie problems trace back to spreading, dryness, or texture issues.

Why Did My Monster Cookies Spread?

Warm dough and softened butter are the leading causes. Chilling the shaped dough before baking solves this almost every time.

Why Are My Monster Cookies Dry?

Too much oat flour buildup from overmeasuring, or overbaking past the soft center stage, both dry cookies out quickly.

Why Aren’t My Monster Cookies Chewy?

Using too much granulated sugar instead of brown sugar reduces the moisture retention needed for a chewy bite.

Problem	Likely Cause	Fix
Cookies spread flat	Warm dough or soft butter	Chill shaped dough 20 to 30 minutes
Dry, crumbly texture	Too many oats or overbaked	Spoon and level oats, pull cookies early
Not chewy enough	Too much granulated sugar	Increase brown sugar ratio
Pale, underbrowned edges	Oven not fully preheated	Preheat fully before baking
Greasy dough	Natural peanut butter used	Switch to commercial creamy peanut butter

How to Store Big Giant Monster Cookies

Store cooled cookies in an airtight container at room temperature for up to five days.

• Layer with parchment paper to keep them from sticking together.
• Add a slice of bread to the container to help retain moisture.

Can You Freeze Monster Cookies?

Yes, both baked monster cookies and raw dough freeze exceptionally well.

Freezing Baked Monster Cookies

Cool completely, layer between parchment in an airtight container, and freeze for up to three months.

Freezing Monster Cookie Dough

Scoop portions onto a tray, freeze until solid, then transfer to a freezer bag and bake from frozen, adding 2 to 3 extra minutes.

For a classic combination that never goes out of style, try our Best Oatmeal Chocolate Chip Cookies. They bring together hearty oats and melty chocolate chips in a slightly smaller, everyday cookie that’s just as satisfying.

Making a double batch for a party, bake sale, holiday cookie exchange, or a house full of hungry cookie lovers? There’s no reason to pull out a calculator and redo every ingredient by hand.

Choose the batch size you need and get perfectly adjusted ingredient amounts in seconds.

Frequently Asked Questions

Are monster cookies gluten-free?

Yes, as long as certified gluten-free oats are used, since the base recipe contains no wheat flour at all.

Why do monster cookies need to rest before baking?

Chilling the dough for 20 to 30 minutes firms up the butter and helps the cookies hold their shape instead of spreading thin.

Can I use quick oats instead of old-fashioned?

Quick oats work in a pinch, but they break down faster and give a softer, less distinctly chewy texture.

Why did my cookies turn out cakey instead of chewy?

Overmeasuring the oats or baking past the soft center stage are the two most common reasons for a cakey texture.

Can I make mini monster cookies instead of giant ones?

Yes, use a standard 2 tablespoon scoop instead of 1/3 cup and reduce the bake time to 9 to 10 minutes.

What’s the best peanut butter to use?

A standard creamy commercial peanut butter gives the most consistent, non-greasy dough compared to natural varieties.

Can I reduce the sugar?

You can trim the granulated sugar slightly, but keep the brown sugar as written to preserve moisture and chew.

Expert Tips for the Best Giant Monster Cookies

• Always chill the dough before baking for maximum thickness.
• Use a kitchen scale for the oats if precision matters to you.
• Underbake slightly and let carryover heat finish the centers.
• Press extra mix-ins on top before baking for bakery-style presentation.
• Let cookies fully cool before storing to prevent condensation and sogginess.

Big Giant Monster Cookies Recipe

Prep Time
20 minutes

Cook Time
12 minutes

Total Time
32 minutes

Yield
20 giant cookies

Ingredients

• 1 cup creamy peanut butter
• 1 cup (2 sticks) unsalted butter, softened
• 1 cup granulated sugar
• 1 cup packed light brown sugar
• 3 large eggs
• 1 tablespoon vanilla extract
• 2 teaspoons baking soda
• 1/2 teaspoon kosher salt
• 4 1/2 cups old-fashioned rolled oats
• 1 cup M&M candies
• 1 cup chocolate chips

Instructions

1. Preheat the oven to 350°F and line two baking sheets with parchment paper.
2. Cream the butter, peanut butter, granulated sugar, and brown sugar until smooth.
3. Beat in the eggs and vanilla until fully combined.
4. Mix in the baking soda and salt, then fold in the oats, chocolate chips, and M&Ms.
5. Chill the dough for 20 to 30 minutes if the kitchen is warm.
6. Scoop 1/3 cup mounds onto the prepared sheets, spacing 3 inches apart.
7. Bake for 11 to 13 minutes until the edges are set and the centers still look soft.
8. Cool on the sheet for 10 minutes before transferring to a wire rack.

Notes

• For extra thick cookies, chill the shaped dough balls for a full hour.
• Certified gluten-free oats keep this recipe fully gluten-free.

Nutrition Information Per Cookie

Each giant monster cookie is a satisfying, bakery-style treat packed with oats, peanut butter, chocolate, and plenty of texture. The nutrition values below are estimated per cookie based on the recipe serving size.

Nutrition	Per Cookie
Calories	312 kcal
Total Fat	16 g
Carbohydrates	37 g
Protein	7 g

Nutrition Disclaimer: Nutrition information is an estimate and may vary depending on the exact ingredients, brands, portion sizes, and number of cookies made. For the most accurate nutritional information, calculate the values using the specific ingredients and quantities you use.

A few degrees can make a surprising difference in cookies this thick. If your oven runs hotter or cooler than the display says, those soft centers and crisp edges can quickly turn into overbaked or overly spread cookies.

Bake with confidence by knowing your oven is actually at the temperature you set.

If chocolate chips are your weakness but you’re ready for something richer, our Best Brown Butter Blondies take that same generous, loaded-cookie spirit and turn it into a deeply buttery dessert bar.

More Cookie Recipes You’ll Love

Loved the oversized, chewy texture and generous mix-ins in these monster cookies? Keep the cookie jar going with these other irresistible cookie favorites.

The Artisan White Chocolate Macadamia Cookies
Buttery, crisp-edged, and packed with creamy white chocolate and crunchy macadamias, these offer a more refined take on the loaded cookie.

Nutri-Bloom Protein Chocolate Chip Cookies
Looking for a lighter everyday option? These soft chocolate chip cookies bring plenty of chocolate flavor with a wholesome, protein-forward twist.

Best Snickerdoodle Recipe
When you’re craving something simpler, these soft, thick snickerdoodles deliver that classic cinnamon-sugar flavor with an irresistibly chewy center.

Shortbread Thumbprint Cookies
Craving something buttery and jam-filled? These tender cookies are a classic treat with a melt-in-your-mouth shortbread texture.

Final Thought

Big Giant Monster Cookies are proof that skipping the flour doesn’t mean skipping the texture.

Between the chewy oats, melty chocolate, and crunchy candy shells, every bite delivers something different.