Preheat your oven to 350°F (175°C).

Line two baking sheets with parchment paper or use silicone baking mats.

Arrange a cooling rack nearby so you can move cookies off the hot sheet quickly.

Pro tip: If your oven runs hot or cold, use an oven thermometer — consistent temperature makes a huge difference in how these cookies spread.

Spoon flour into your measuring cup and level with the back of a knife (don’t scoop directly from the bag).

Measure the oats, sugars, peanut butter, and chocolate chips into separate bowls so everything’s within reach.

Pro tip: Accurate flour measurement prevents dense cookies. A light hand here keeps them soft and chewy — just what you want for really good cookies.

In a large bowl, add the softened butter, creamy peanut butter, brown sugar, and granulated sugar.

Beat with a hand mixer or stand mixer on medium speed until the mixture is light and a little fluffy — about 2 minutes.

Scrape down the bowl with a rubber spatula so no pockets of butter or sugar remain.

Pro tip: Don’t use melted butter. Softened (not warm) butter traps air when creamed, giving you that tender, slightly puffy texture.

Add the eggs one at a time, beating briefly after each until incorporated.

Mix in the vanilla extract until the batter looks smooth and glossy.

Pro tip: Use room-temperature eggs for a smoother emulsion — they incorporate more easily into the butter mixture.

In a separate bowl, whisk together the all-purpose flour, baking soda, and salt.

Stir the oats into the dry mix so they’re evenly distributed.

Add the dry mix to the wet ingredients in two additions, stirring gently after each until just combined.

Fold in the chocolate chips and most of the M&M’s, leaving a few aside for topping.

Pro tip (key step): Stop mixing as soon as the flour disappears. Overworking the dough develops gluten and will make cookies tougher — you want tender chewiness instead.

Use a 1½ tablespoon cookie scoop (or two spoons) to portion dough into even mounds.

Place dough balls about 2 inches apart on the prepared baking sheets.

Gently press a couple of reserved M&M’s into the top of each cookie for a pretty, festive look.

Pro tip: If you prefer thicker cookies, chill the scooped dough for 15–20 minutes before baking — it slows spreading and gives a chunkier center.

Bake one sheet at a time on the center rack for 9–12 minutes. Start checking at 9 minutes.

Look for edges that are set and lightly golden while the centers still look slightly soft — they’ll finish cooking on the hot sheet.

If baking two sheets at once, rotate them halfway through for even browning.

Pro tip (key step): Resist the urge to overbake — cookies will firm up as they cool. Pull them when the centers still jiggle a little.

Let the cookies rest on the baking sheet for 4–5 minutes so they set without breaking.

Transfer them to a cooling rack to finish cooling completely.

Store cooled cookies in an airtight container at room temperature for up to 4 days, or freeze for longer.

Pro tip: Place a slice of bread in the container with the cookies to help keep them soft — the cookies will absorb moisture from the bread and stay chewy.