Once the dough is smooth, I gently fold in the M&Ms and white chocolate chips. This step always feels like decorating a Christmas tree—suddenly everything becomes colorful and joyful. I save a handful of M&Ms for topping the cookies later because I’ve learned that adding a few on top before baking makes them look like bakery-style cookies. The dough will be sticky, but don’t worry—that’s exactly how it should be.
I line a baking sheet with parchment paper and use a cookie scoop to portion out the dough. If I want big, puffy cookies, I scoop generously. If I want smaller ones for gifting or cookie trays, I scoop a little lighter. I always make sure to space them apart since they spread slightly while baking. Before putting them in the oven, I gently press 3–4 extra M&Ms on top of each scoop. This makes them look so festive once they bake.
As the cookies bake, the whole kitchen fills with the smell of warm vanilla and melting chocolate. They puff up beautifully, and the edges turn just the faintest hint of golden pale. When I pull them from the oven, I always let them cool for a few minutes on the baking sheet before transferring them to a rack. This helps them set and keeps them soft and chewy in the middle. The result is a beautiful tray of Christmas cookies that look far more impressive than their simple ingredients suggest.
Pro Tips for Best Results
I tested this recipe three different ways, and one thing I learned is that chilling the dough for 10–15 minutes makes a noticeable difference. When I skipped chilling, the cookies spread a bit more and baked thinner. They were still delicious, but if you want thick, soft cookies, a quick chill really helps. It also makes the dough easier to scoop.
Another tip: don’t bake these cookies until they look fully done. With cake mix cookies, the trick is to pull them out when the edges look set but the centers still look slightly soft. I used to leave them in until they looked cooked through, and they ended up cakey instead of chewy. Removing them earlier gives them that perfect soft-baked texture.
One more helpful thing I learned is to mix the dough gently. Overmixing can make the cookies tough. I stir only until the ingredients come together, especially after adding the soda. The lighter and fluffier the batter stays, the softer the final cookies will be.
Finally, add decorations before baking rather than after. I tried pressing in extra M&Ms while the cookies were hot, but they melted and created little craters. Adding them just before baking helps them keep their shape and color beautifully.
Common Mistakes to Avoid
I made this mistake the first time—don’t add oil or butter! I know it feels strange to make cookies without any, but cake mix cookies rely on the soda and eggs to create their texture. When I experimented by adding butter, the cookies spread too much and turned greasy. Stick to the recipe and they’ll turn out perfect.(See the next page below to continue…)