These one-bowl chewy M&M cookie bars come together fast with simple ingredients you already have. Soft, chewy, and ready in just 30 minutes, they’re perfect for an easy dessert or sweet treat anytime.
You can easily change the color of the M&M’s to match any holiday or celebration. I used festive red and green for the holidays, but feel free to swap them for any colors you like. 🎄🍫
For more easy holiday recipes try my Assorted butter cookies, Almond snowball cookies and Cranberry Cheesecake Bars.
Why You’ll Love These One-Bowl M&M Cookie Bars
These cookie bars are soft, chewy, and incredibly easy to make. Everything comes together in just one bowl, making cleanup quick and stress-free. Perfect for busy days, bake sales, or last-minute desserts.
Ingredients
- Butter: Use unsalted butter softened to room temperature for the best creamy texture and flavor control.
- Sugars: A mix of brown sugar and white sugar gives these bars the perfect chewy center with crisp edges.
- Baking Soda: Use baking soda, not baking powder, to help the cookie bars spread and stay chewy.
- Flour: All-purpose flour works best for the right structure and soft bite.
- M&M’s: Add color and crunch—use any festive colors you like.
- Chocolate Chips: Semi-sweet chocolate chips balance the sweetness perfectly.
See recipe card below for a full list of ingredients and measurements.
How to Customize M&M Colors for Holidays
One of the best things about these cookie bars is how easy they are to customize. Simply swap the M&M colors to match any holiday or celebration—red and green for Christmas, pastel shades for Easter, or team colors for parties.
Baking Tips for Soft and Chewy Cookie Bars
Do not overbake—slightly underbaked centers will set as the bars cool. Let the bars cool before slicing for clean edges and the best texture.
Storage
Store cookie bars in an airtight container at room temperature for up to 4 days. You can also freeze them for longer storage and enjoy later.
Recipe video
📖 Recipe
One-Bowl Chewy M&M Cookie Bars (in 30 minutes)
Ingredients
- ½ cup (1 stick) unsalted butter, softened
- ½ cup brown sugar
- ¼ cup granulated sugar
- 1 large egg
- 1 ½ cup all purpose flour
- ½ teaspoon baking soda
- ¼ teaspoon salt
- ½ cup M&M plus more for sprinkling on top
- ½ cup semi-sweet chocolate chips plus more for sprinkling on top
Instructions
- Preheat your oven to 325°F (165°C). Line an 8×8-inch baking pan with parchment paper, leaving extra overhang on the sides to easily lift the bars out later.
- In a large bowl, mix the softened unsalted butter, brown sugar, and white sugar until smooth and creamy.
- Add the egg and mix until fully combined.
- Stir in the all-purpose flour, baking soda and salt, then gently mix in the just until no dry flour remains.
- Fold in the M&M’s and semi-sweet chocolate chips.
- Spread the dough evenly into the prepared pan and press lightly. Add extra M&M’s and chocolate chips on top.
- Bake for 22–25 minutes, or until the edges are set and the center is slightly soft.
- Let cool completely in the pan, then lift out using the parchment overhang. Slice into bars and enjoy.
Video
Notes
- Do not overbake — the center will continue to set as it cools.
- Measure flour correctly to avoid dry bars.
- Let the bars cool fully before cutting for clean slices.
- Use parchment paper overhang for easy removal.
- M&M colors may bleed slightly when warm — this is normal.
