Recipe

Monster Cookies!!

Chunky peanut butter–oatmeal cookies studded with M&M’s and chocolate chips

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These Monster Cookies are a mash-up of peanut butter, oatmeal and choc chip cookies: hand-mixed, quick to make and piled with M&M’s and chocolate chips. The dough doesn’t need chilling and bakes into large, chewy cookies with crisp edges.

About the key ingredients

Use commercial sandwich-style peanut butter (eg Jif/Skippy/Sun-Pat), not natural peanut butter. Use ordinary rolled oats (not quick-cooking or steel-cut). Plain/all-purpose flour and baking soda (bicarbonate of soda) are used; brown sugar provides caramel flavour and colour. Regular M&M’s (plain) and chocolate chips are the classic add-ins.

Baking notes

Melt the butter until mostly melted but still milky yellow (not clear), then stir to finish so the butter stays cool enough for immediate mixing. The dough is designed to be mixed by hand and baked without refrigeration. If dough is too sticky to roll, chill the bowl for about 5 minutes to firm it up.

What Makes This Recipe Work

These Monster Cookies are built for texture and spectacle: commercial peanut butter gives body and binding, ordinary rolled oats add chew and bite, and both M&M’s and chocolate chips deliver pockets of chocolate and colour. The dough is mixed by hand and deliberately designed to be baked straight away—no overnight chilling required—so you get big, tall cookies with crisp rims and a soft, chewy interior without extra wait time.

Ingredient Notes

Use a sandwich-style commercial peanut butter rather than a natural variety. The stabilisers and sweeteners in commercial brands keep the dough cohesive and prevent it becoming dry and crumbly. Ordinary rolled oats are specified for chewiness and texture; quick-cooking oats will break down too much and steel-cut oats are unsuitable. Brown sugar is the caramelising sweetener here, contributing to both flavour and the attractive golden colour at the edges. Plain all-purpose flour and a little baking soda provide structure and lift, while the mix-in trio of M&M’s and chocolate chips gives the classic chunky look and chocolate pockets that define a monster cookie.

How to Get the Best Result

There are a few small technique points the recipe leans on. Melt the butter just until mostly melted but still milky yellow; stirring off the heat finishes the melt while keeping the butter cool enough to combine immediately. The dough is intentionally hand-friendly—mix by hand with a wooden spoon until the flour is no longer visible; small lumps of peanut butter are fine and won’t hurt the final texture.

If you find the dough too sticky to roll, don’t overwork it—pop the mixing bowl into the fridge for about five minutes to firm it slightly. For even baking when you run two trays at once, rotate tray positions between the oven racks halfway through the bake so both trays achieve similar colour. Aim for golden edges for that crisp perimeter and a light golden surface; these cookies are forgiving if you leave them in a touch longer for more colour.

When they come out of the oven, allow the cookies to cool on the baking tray for about ten minutes before transferring to a wire rack. While still hot, press the reserved M&M’s into the tops at an angle so they sit partly embedded; adding a few extra chocolate chips on top while the cookies are hot helps the melted chip base adhere as the cookie cools.

Serving Ideas

These cookies are large and chunky by design and show best when the tops are studded with candy and chips. Serve them warm for maximum chew and visible melted chocolate pockets, or at room temperature once they’ve been allowed to set and the added M&M’s are fully seated. They make a colourful bake sale item or a crowd-pleasing treat for a casual gathering.

Storage / Make-Ahead

The original recipe does not include storage or make-ahead instructions. Because the dough is designed to be baked without refrigeration, consider making and baking just before you need them. If you want to prepare ahead, the recipe’s guidance warns that chilling the mixed dough briefly is used only to manage stickiness, not as a required step for development.

What to Watch For

  • Use the specified types of peanut butter and oats — substitutions here will change texture and dough behaviour.
  • Melt the butter carefully so it remains cool enough to mix immediately; over-heated clear butter will alter the dough temperature.
  • Press extra M&M’s and chips into the cookies while still hot so they sit attractively and adhere as the cookies cool.

These notes focus on small treatments that make a reliable, chunky monster cookie every time. Follow the recipe’s ingredient choices and its simple handling cues for the best combination of crisp edge and chewy centre.

A finished serving of Monster Cookies!!
Let's cook

Monster Cookies!!

Cook15 minutes
Servings17 cookies
Scale

Ingredients

Instructions

  1. Preheat oven to 180°C / 350°F (160°C fan-forced). Line baking trays with paper.
  2. In a medium bowl, stir together the flour, rolled oats, baking soda and salt; set aside.
  3. In a large microwave-safe bowl, barely melt the butter in short bursts (about 20 seconds), leaving some butter lumps; stir to finish melting so the butter is milky yellow, not clear.
  4. Add peanut butter, brown sugar, the cold egg and vanilla into the melted butter and mix by hand until combined. Small peanut butter lumps are fine.
  5. Pour the dry ingredients into the wet ingredients and stir with a wooden spoon until mostly incorporated. Add the chocolate chips and 1 cup (200g) M&M’s, reserving about 1/4 cup for decorating; mix until the flour is no longer visible.
  6. Scoop and roll the dough into 17 balls, about 3 tablespoons each (approximately 4.5 cm / 1.8" diameter). Place on prepared trays about 7.5 cm / 3" apart. If the dough is too sticky to roll, chill the bowl for about 5 minutes.
  7. Bake two trays at a time for 15 minutes, switching tray positions between racks during baking so they brown evenly. The edges should be golden and the surface light golden.
  8. Cool the cookies on the tray for 10 minutes, then transfer to a wire rack and cool another 10 minutes. While still hot from the oven, press the reserved M&M’s into the tops at an angle so they sit partly embedded; place extra chocolate chips on top so the heat melts their base and they adhere.
Nutrition

Estimated nutrition per serving

Estimated
Nutrition estimate unavailable from the supplied ingredient details.

ESTIMATE: Insufficient ingredient weight details to provide reliable nutrition estimates. Key amounts for flour, oats, brown sugar, butter and peanut butter are not specified, so Calories, Protein, Carbohydrates, Fat and Fiber cannot be calculated accurately from the supplied information.

Helpful Tips

  • Use commercial sandwich-style peanut butter (not natural) so the dough stays cohesive rather than dry and crumbly.
  • Choose ordinary rolled oats for chewiness and texture—avoid quick-cooking or steel-cut oats.
  • Melt the butter just until mostly melted and still milky yellow; stir off the heat to finish so the butter isn’t too hot when mixed.
  • If the dough is too sticky to roll, chill the mixing bowl for about 5 minutes rather than overworking the dough.
  • Bake two trays at once? Switch their positions between racks during baking to ensure even browning.
  • Press reserved M&M’s and extra chocolate chips into the cookies while they’re still hot so they sit partly embedded and stick as they cool.

Frequently Asked Questions

Can I use natural peanut butter?

No—use a commercial sandwich-style peanut butter. Natural peanut butter can make the dough dry and crumbly.

Do I need to chill the dough?

No. The dough is formulated to be baked without refrigeration. Chill the bowl for about 5 minutes only if the dough is too sticky to handle.

What oats should I use?

Use ordinary rolled oats for the intended chew and texture. Avoid quick-cooking and steel-cut oats.

How do I keep the candies and chips on top?

Press the reserved M&M’s and extra chocolate chips into the cookie tops while the cookies are still hot so they sit partly embedded and adhere as they cool.

Can I mix this dough by hand?

Yes. The recipe is designed to be mixed by hand; small lumps of peanut butter in the dough are fine.

How do I get crisp edges and a chewy middle?

Aim for some golden colour on the edges—the cookies are forgiving if baked a little longer for colour, which helps create crisp edges while the centre stays chewy.

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