Small Batch M&M Cookie Bars

Think of these small batch M&M cookie bars as a cross between your favorite chocolate chip cookie and a shiny-top blondie. They’re made with a thick, no-chill cookie dough packed with M&M candies and chocolate chips, with plenty of buttery brown sugar flavor to remind you it’s a cookie. Baked in a 6-inch pan, the bars come out golden with a satisfying chewy center.

Not Your Ordinary Cookie Bar

The colorful M&Ms aren’t the only thing that makes these cookie bars special. While they may look like my small batch blondies with their shiny tops, I developed them to eat more like a chewy chocolate chip cookie.

You get notes of caramel from brown sugar and melted butter, with plenty of vanilla to round out the flavor. Inside, the bars bake up thick and chewy, but in my house, we call dibs on the crisp corner pieces.

Since the dough bakes in a 6-inch square pan, there’s no need to chill it to control cookie spread. And you can keep the mixer in the cabinet for this one. This easy one-bowl recipe may have you opting for cookie bars the next time a cookie craving hits.

How To Make M&M Cookie Bars

To start, melt the butter in the same bowl you’ll be making the dough in. Add both sugars and whisk well until you have a paste-like mixture. Whisking the sugars into the warm butter helps dissolve them slightly, which gives the bars their glossy tops.

Mix in the egg yolk and vanilla, then sprinkle the dry ingredients right over the top. The dough isn’t quite as thick as classic cookie dough, but I still switch to a spatula to avoid over-mixing the flour.

Add the M&Ms and chocolate chips to the dough, and fold until just combined. Transfer the dough to a fully lined pan and use the spatula to push it into all of the edges.

Inevitably, there will be obvious bare spots on top. Fill those with a few more chocolate candies to make sure every square has a pretty top. And to use up any leftover M&Ms, make a batch of my chewy monster cookies next.

Baking And Slicing The Cookie Bars

As the cookie bars bake, you’ll notice they puff up quite a bit. They’ll settle as they cool and develop that satisfying cookie-like chew. Keep a close eye on the bake time, though. Overbaking is a surefire way to take the bars from chewy to dry and crunchy. They’re done when lightly golden, with a few moist crumbs clinging to a toothpick.

Leave the cookie bars in the pan to cool completely before you slice them. Once set, they’ll cut cleanly into squares without crumbling.

Small Batch M&M Cookie Bars

Small batch M&M cookie bars made with buttery brown sugar cookie dough, M&M candies, and chocolate chips. The easy one-bowl bars bake in a 6-inch pan with crisp edges, chewy centers, and glossy tops.

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by Erin Cernich

Yield9 Bars

Prep15 minutes minutes

Cook22 minutes minutes

Total Time37 minutes minutes

Equipment

• ▢
  6-Inch Square Cake Pan
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  Odd Size Measuring Spoons

Ingredients

• ▢ ¼ cup unsalted butter, melted
• ▢ ¼ cup light brown sugar, packed
• ▢ 3 tablespoons granulated sugar
• ▢ 1 large egg, room temperature
• ▢ 1 teaspoon vanilla extract
• ▢ ¾ cup, plus 2 tablespoons all-purpose flour
• ▢ ⅛ teaspoon baking powder
• ▢ ⅛ teaspoon baking soda
• ▢ ¼ teaspoon salt
• ▢ ¼ cup M&Ms
• ▢ 3 tablespoons semi-sweet chocolate chips (regular or mini)

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Instructions

 

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  Preheat the oven to 350F degrees and adjust the rack to the middle position. Line a 6-inch square cake pan completely with a piece of parchment.
To line the pan, cut the parchment paper in half lengthwise, then lay in the pan. This will leave enough overhang to easily pull the bars out of the pan.
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  Add the butter to a microwave-safe mixing bowl and heat until melted. Add both sugars and mix until the butter has cooled and the mixture is paste-like. Add the egg and vanilla and mix until the egg is fully combined.
  1/4 cup unsalted butter, melted, 1/4 cup light brown sugar, packed, 3 tablespoons granulated sugar, 1 large egg, room temperature, 1 teaspoon vanilla extract
  
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  Sprinkle the flour, baking powder and baking soda, and salt over the top of the wet ingredients. Use a spatula to combine until no dry streaks remain. Fold in the chocolate chips and M&Ms until just combined. The dough will be thick and sticky.
  3/4 cup, plus 2 tablespoons all-purpose flour, 1/8 teaspoon baking powder, 1/8 teaspoon baking soda, 1/4 teaspoon salt, 1/4 cup M&Ms, 3 tablespoons semi-sweet chocolate chips
• ▢
  Transfer the dough into the prepared pan, and use a spatula to press it evenly into the pan and into all the corners. Press more M&Ms on top to fill in any bare spots. Bake the bars for 22 to 24 minutes, or until the edges and top are lightly golden, and a toothpick inserted in the middle comes out mostly clean.
  
They will be puffy as they bake and will settle as they cool. Like any baked bar, the middle piece will be the chewiest.
• ▢
  Cool the cookie bars in the pan set on a wire rack completely, then carefully lift out of the pan. Cut into desired squares (I cut into nine 2-inch squares).
  
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  Store the bars in a covered container at room temperature for up to 5 days.

Notes

• Serving Size – This is a small batch recipe that can be doubled. Use an 8 or 9-inch square pan and increase the bake time by 3 to 5 minutes.
• M&Ms – Use any variety or color of M&M to match a special occasion or holiday. 
• Make Ahead – The cookie dough can be made ahead of time and either refrigerated for up to 2 days or wrapped in plastic and frozen for up to 3 months. If freezing, thaw in the refrigerator, then bring to room temperature before transferring to the pan to bake.
• Freezing – Place baked and cooled bars in a freezer bag and freeze for up to 3 months. Thaw at room temperature.

Nutrition information is calculated by a third-party and should only be considered an estimate and not a guarantee.