Ingredients
Dry:
1 ½ cups (135 g) rolled oats
1 cup (125 g) all-purpose/plain flour
1 tsp baking soda
½ tsp salt
Wet:
½ cup (115 g) unsalted butter, softened
½ cup (100 g) brown sugar
½ cup (100 g) white/granulated sugar
¾ cup (190 g) peanut butter (smooth or crunchy)
2 large eggs
1 tsp vanilla extract
Mix-ins (the “monster” part – adjust as you like):
½ cup (90 g) chocolate chips
½ cup (90 g) candy-coated chocolates (like M&M style)
Optional: ¼ cup (30 g) chopped nuts or extra chips
Step-by-Step Instructions
1. Get the Oven Ready
Preheat your oven to 350°F (180°C).
Line 2 baking sheets with parchment paper or a silicone baking mat.
This stops the cookies sticking and helps them bake evenly.
2. Mix the Dry Ingredients
In a medium bowl, combine:
Oats
Flour
Baking soda
Salt
Stir with a spoon or whisk until everything is evenly mixed. Set aside.
3. Cream the Butter, Sugars, and Peanut Butter
In a large mixing bowl:
Add softened butter, brown sugar, and white sugar.
Beat with an electric mixer (or a sturdy spoon and some muscle) until:
The mixture looks light, creamy, and fluffy – about 2–3 minutes with a mixer.
Add the peanut butter and beat again until smooth.
This creamy base is what makes your delicious monster cookies recipe you’ll love rich and chewy.
4. Add Eggs and Vanilla
Crack in the eggs, one at a time, mixing well after each.
Add the vanilla extract and mix again until smooth.
Now your wet mixture should be thick, glossy, and well combined.
5. Add the Dry Ingredients
Pour the dry mixture (oats + flour + baking soda + salt) into the wet bowl.
Mix on low speed or stir with a spatula just until it’s combined – don’t overmix.
You should have a thick, scoopable cookie dough.
6. Stir in the “Monster” Mix-ins
Now for the fun part:
Add the chocolate chips and candy-coated chocolates.
Stir gently until they’re spread through the dough.
If you want extra colour on top, save a small handful of candies to press into the tops of the cookies before baking.
7. Scoop and Shape
Scoop tablespoon-sized balls of dough and place them on the prepared baking sheets.
Leave space between them – they spread as they bake.
For larger bakery-style cookies, use 2 tablespoons of dough each and space them even further apart.
If you like a neater look, gently flatten each ball slightly with your fingers or the back of a spoon.
For extra cuteness, press a few extra candy pieces on top of each cookie.
8. Bake
Bake for 10–12 minutes for smaller cookies, 12–14 minutes for larger ones.
You’re looking for:
Lightly golden edges
Centres that still look slightly soft – they’ll firm up as they cool.
Don’t overbake if you like them chewy.
Ask an adult to help take the hot trays out of the oven.
9. Cool and Enjoy
Let the cookies cool on the baking sheet for about 5 minutes.
Transfer them carefully to a wire rack to cool completely (or at least until they’re safe to eat!).
Now you’ve got a tray of warm, colourful, chewy monster cookies. 😍
Easy Variations
Once you’ve tried this delicious monster cookies recipe you’ll love, you can customise it:
1. Peanut-Free Option
Swap peanut butter for sunflower seed butter, cookie butter, or another nut/seed spread (as long as everyone eating them is okay with it).
Flavour will change slightly, but they’ll still be great.
2. Extra-Chocolate Monster Cookies
Use all chocolate chips (milk, dark, or white).
Add 2 tbsp cocoa powder to the dry ingredients for a chocolate base.
3. Oatier Texture
Want more “granola bar meets cookie”?
Reduce flour to ¾ cup (95 g)
Increase oats by ¼ cup (about 20–25 g)
4. Add-Ins Ideas
Mix and match:
Mini marshmallows (press them into the top right before baking)
Crushed pretzels for salty crunch
Chopped nuts (walnuts, pecans, etc., if no one has allergies)
Practical Tips for Perfect Monster Cookies
Tip 1: Don’t Melt the Butter
Use softened butter (room temperature), not melted.
Melted butter can make the cookies spread too much and go thin and greasy.
Tip 2: Chill the Dough (Optional but Helpful)
If your dough feels very soft or your kitchen is warm:
Chill the dough in the fridge for 20–30 minutes before baking.
This helps the cookies hold their shape better and bake up thicker.
Tip 3: Rotate the Trays
If you’re baking two trays at once:
Swap them halfway through baking (top to bottom, front to back)
This helps them bake more evenly, especially in older ovens.
Tip 4: Slightly Underbake for Chewy Centres
Take them out when the edges are just golden and the centres still look a tiny bit soft.
They’ll finish cooking from the heat of the tray as they cool.
Perfect if you like your monster cookies soft, chewy, and a bit fudgy.
Tip 5: Storing Your Cookies
Let them cool completely.
Store in an airtight container at room temperature.
They’ll stay good for about 4–5 days (if they last that long).
For longer storage, freeze baked cookies or dough balls:
Freeze dough balls on a tray, then pop into a bag/container.
Bake from frozen, adding 1–2 extra minutes.
Conclusion
This delicious monster cookies recipe you’ll love gives you everything:
Chewy texture
Crispy edges
Pockets of chocolate and colourful candy
Super easy steps you can repeat any time a cookie craving hits
They’re perfect for:
Lunchbox treats
Bake sales
Movie nights
Sharing with friends and family (or… not sharing 👀)