clock clock iconcutlery cutlery iconflag flag iconfolder folder iconinstagram instagram iconpinterest pinterest iconfacebook facebook iconprint print iconsquares squares iconheart heart iconheart solid heart solid icon
cookie bars on wax paper

M&M Cookie Bars

  • Author: Erin Clarkson
  • Prep Time: 10 minutes
  • Cook Time: 25 minutes
  • Total Time: 35 minutes
  • Yield: 12 servings 1x
  • Category: Cookies
  • Method: Baking
  • Cuisine: American


Super easy M&M cookie bars are thick and chewy, and loaded with M&Ms and chocolate chunks. These cookie bars are all the taste and texture of a cookie, but baked into a bar!


  • 100g unsalted butter, melted and cooled (re-weigh after melting and add a little extra butter if needed)
  • 120g light or dark brown sugar
  • 45g granulated sugar
  • 2 large egg yolks, at room temperature (about 45g egg yolks)
  • 1 tsp vanilla bean paste or vanilla extract
  • 135g all-purpose flour
  • ¼ tsp baking powder
  • 2g salt (½ tsp kosher salt)
  • 180g m&ms plus a few more for the tops, optional
  • 85g dark chocolate, chopped


  1. Preheat the oven to 350°f / 180°c. Grease and line an 8" (20cm) non stick baking pan, leaving the parchment extending over the sides to form a sling. Secure with binder clips if desired.
  2. In a medium bowl, combine the melted butter, brown sugar, granulated sugar, egg yolks, and vanilla. Whip well with a whisk or a handheld electric mixer until the mixture has thickened and lightened in colour slightly. 
  3. Add the flour, baking powder and salt, and mix to combine with a spatula until just a few streaks remain. 
  4. Add in the m&ms and chopped chocolate and mix to incorporate with a spatula.
  5. Press the dough into the prepared pan, smoothing down with an offset spatula. Add a few extra m&ms to the top of the cookie if desired.
  6. Bake the cookie bars for 20 to 22 minutes, until the top of the cookie is golden brown and set and the edges have started to firm up slightly. If you would like the edges of your cookie bar to be crispy, bake for a little longer.
  7. Remove the cookie bars from the oven and leave to cool in the pan on a wire rack. Remove from the pan using the parchment paper sling. Cut into pieces using a sharp knife.
  8. Store cookie bars in an airtight container at room temperature for up to 3 days.

Keywords: Cookie bars, m&m cookies, m&m cookie bars