Preheat the oven to 375°F. Line two baking sheets with silicone baking mats or parchment paper or spray with cooking spray.

In a large bowl, using a stand mixer with the paddle attachment or a hand mixer, cream together the butter and sugars for 3-4 minutes. Add the eggs in one at a time and beat completely before adding in the second one. Then add the vanilla and mix until combined.

In a separate bowl combine the flour, baking soda and salt and stir mix just until combined. Add it to the butter mixture and mix just until combined. Fold in the chocolate chips and M&M’s. Refrigerate dough for 15 to 30 minutes before baking.

Using a large cookie scoop (about 2-3 Tablespoons), scoop the cookie dough onto the baking sheet about 2 inches apart.

Bake for 8-10 minutes, or until the edges are barely golden brown. Allow cookies to set on pan for 2 minutes, and then remove to a cooling rack.