Dessert

M&M Cookie Bars Recipe

ByMaya Arden March 10, 2026March 10, 2026

Introduction

These M&M Cookie Bars are a colorful and delicious treat perfect for satisfying your sweet tooth. They combine a buttery cookie base with melty chocolate chips and vibrant M&Ms for a fun twist on classic cookie bars.

The image shows several square pieces of thick, golden brown cookie bars stacked casually on a white wooden board placed on a white marbled surface. Each cookie bar has a soft, crumbly texture with a light yellow interior and a golden crust. Brightly colored red, pink, and white candy-coated chocolates are mixed into the dough, scattered on the top and inside of the bars. There are visible small pockets of melted chocolate chunks within the bars, adding a darker contrast to the light cookie dough. The overall look is warm and inviting, with a few candy pieces also scattered beside the board on the marbled surface. photo taken with an iphone --ar 4:5 --v 7

Ingredients

1/2 cup softened butter
1/2 cup brown sugar

1/4 cup white sugar
1 tsp vanilla extract

1 egg
1/3 tsp baking soda

1/3 tsp salt
1 cup flour
1/2 cup chocolate chips

1/2 cup M&Ms

Instructions

Step 1: Preheat your oven to 350°F (175°C). In a bowl, combine the softened butter, brown sugar, and white sugar until the mixture is smooth.
Step 2: Beat the mixture fully to incorporate air. Add the vanilla extract and egg, then beat again until well blended.

Step 3: In a separate bowl, whisk together the flour, baking soda, and salt. Gradually add the dry ingredients to the wet mixture, beating until fully combined.
Step 4: Stir in the chocolate chips and most of the M&Ms, keeping a handful reserved for topping the bars.
Step 5: Spread the cookie dough evenly into an 8×6 inch or 9×7 inch baking pan. Sprinkle the reserved M&Ms evenly over the top.

Step 6: Bake in the preheated oven for 18–20 minutes, or until the surface turns golden brown.
Step 7: Let the cookie bars cool completely in the pan before slicing into squares to serve.

Tips & Variations

For extra chewiness, slightly underbake the bars by removing them from the oven when the edges are set but the center is still soft.

Substitute peanut butter M&Ms for a nutty flavor twist.
Add chopped nuts like walnuts or pecans to the dough for added texture.
Use mini M&Ms throughout for more even chocolate distribution.

Storage

Store the cookie bars in an airtight container at room temperature for up to 3 days. They can also be refrigerated for up to a week; bring to room temperature before serving for the best texture. To reheat, warm individual pieces briefly in the microwave until soft.

How to Serve

The image shows seven square pieces of colorful cookie bars stacked on a dark wooden board with a rope loop handle. Each cookie bar has two visible layers: a light golden brown top layer scattered with small red, pink, and white candy-coated chocolate drops, and a middle chocolate chip layer running horizontally through the soft, pale yellow base. The surface beneath the board is a white marbled texture, with scattered candy drops in red and white around the board. In the background, there are blurred white bowls containing more candy drops and a dark liquid in a white cup on a matching saucer. Photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use salted butter instead of unsalted?

Yes, but omit or reduce the additional salt in the recipe to avoid oversalting your cookie bars.

Can I freeze these cookie bars?

Absolutely. Wrap the cooled bars tightly in plastic wrap and place them in a freezer-safe container. They keep well frozen for up to 2 months. Thaw at room temperature before serving.