These M&M cookie bars are packed with chocolate chips, white chocolate chips, and Christmas M&Ms. They are ideal for holiday trays and cookie trays, as well as for starting your holiday baking.

There is nothing I love more than a cookie that doesn’t require a lot of effort but can be made for a crowd and everyone will rave about it. All you need to do is press everything into a 9×13 pan; it requires no rolling or chilling of the dough. What’s not to love about that? In the end, you will end up with a super soft, chewy cookie loaded with M&Ms, white chocolate, and semi-sweet chocolate chips.

Ingredients for making M&M Cookie Bars

  • Unsalted Butter I like to used unsalted butter and then add salt into the recipe if you are using salted butter omit the salt.
  • Sugar white granulated sugar
  • Brown Sugar use golden brown sugar firmly packed
  • Eggs I like to use farm-fresh eggs, but any eggs will do; if you use extra-large eggs, they will give you a slightly softer cookie dough.
  • Pure Vanilla You can use any vanilla extract, or if you have pure vanilla, that will give you the best flavor.
  • I always use all-purpose flour; if you have a favourite brand, then use that.
  • Baking Soda Make sure the baking soda you are using is fresh for the best results.
  • Salt I like to use sea salt or kosher salt.
  • Christmas M&M’s I like to buy them as soon as they become available because they become harder to find as the holiday season gets closer.
  • Mini Chocolate Chips I find that in cookie bars, the mini chocolate chips work best for when you are cutting the bars into slices later.
  • White Chocolate Chips I like to use Nestle white chocolate chips because I find other brands sometimes burn a little quicker than others.

How to make M&M Cookie Bars

  • Wet ingredients In a large bowl, cream together butter, granulated sugar, and brown sugar for 1 minute until fluffy. Add vanilla and eggs and combine.
  • Dry Ingredients In a separate bowl, combine the flour, salt, and baking soda and stir.
  • Assemble Add in M&M’s and chocolate chips, and add dough to line a 9 x 13 pan. Place a few extra M&Ms and chocolate chips on top. (And, of course, some for testing; you know you want some.)
  • Bake Bake for 30-35 minutes, or until the top is barely golden brown, then cool completely before cutting into slices.

Baking Tips and suggestions

  • Line the pan Make sure to line your baking pan with foil or parchment paper; this will help your bars cook more evenly and will make cleanup a breeze.
  • Thinner Bars If you bake them in a 15 x 10 pan, you can have a thinner bar, which is how I like them, but for a thicker bar, you can use a 9 x 13 pan. It really comes down to personal preference.
  • Extra M&M’s on top To make the top of your cookie bars look really nice, you can add a few before cooking or you can add them right out of the oven. Both are great options.
  • Underbaked or overbaked you want to remove the bars from the oven when the top becomes just barely golden; they will look like they are underdone, but as they cool down, they will continue to bake. You don’t want to overcook them, or you won’t achieve a nice chewy center.

Variations

If you’re looking for something different, try the holiday-colored M&M’s or something that you can make year-round.

  • Glaze a powdered sugar glaze simply drizzle over the bars once they have cooled.
  • Chocolate Chips Milk chocolate, semisweet chocolate, butterscotch chocolate, or white chocolate chips can all be used.
  • Season You can make these bars anytime of the year, and the nice thing is you can find colors of M&M’s for almost every holiday or occasion.
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The Best M&M Cookie Bar

These M&M cookie bars are packed with chocolate chips, white chocolate chips, and Christmas M&Ms. They are great to start your holiday baking and great for holiday trays and cookie trays.
5 from 2 votes
Prep Time 15 mins
Cook Time 30 mins
Total Time 40 mins
Course cookies
Cuisine American
Servings 24 Bars

Ingredients
  

  • 1 cup unsalted butter room temperature
  • 1 cup brown sugar
  • ¾ cup granulated sugar
  • 2 large eggs
  • 2 tsp pure vanilla
  • 3 cups all-purpose flour
  • 1 tsp baking soda
  • ¼ tsp kosher salt
  • ½ cup chocolate chips plus more for tops if desired
  • ½ cup white chocolate chips plus more for tops if desired
  • 1 cup M&M's plus more for tops if desired

Instructions
 

  • Preheat the oven to 325°F. In a large bowl using a mixer, cream together the butter and sugars for 1 minute. Add the eggs and vanilla and mix until combined.
  • Add the flour, baking soda and salt and stir mixture just until combined. Fold in the chocolate chips and M&M’s (saving about 1/4 cup for the top).
  • Spray with non-stick spray. Scoop cookie dough into the pan and press down evenly. Then place extra M&M’s and chocolate chips on the top.
  • Bake for 30-35 minutes, or until the top is barely golden brown. Allow to cool completely, then remove and slice.
Keyword Bar, Cookies, Easy, M&M’s