In a large bowl, whisk together flour, baking soda, and salt. Set aside.
In a large bowl using an electric mixer, cream together butter, shortening, and sugars on medium speed, until light and fluffy. Add vanilla extract; beat until well combined.
Beat in eggs, one at a time, until well combined.
Add flour mixture to wet ingredients; mix just until combined. Gently fold in ¾ cup mini M&M's candies.
Scoop dough into tablespoon rounds, or use a #50 disher to scoop balls of dough. Place on ungreased cookie sheet or silicone mat/parchment paper lined baking sheet. Top each dough ball with a few M&M's candies.
Bake for 9-10 minutes, or until edges are a light golden brown. Cookies may appear soft in the middle, but they will set as they cool.
Cool cookies on baking sheet for a few minutes; transfer to a wire rack to cool completely. Eat & Enjoy!
Notes
M&M Cookies should be stored in an airtight container and will keep 5+ days.Recipe adapted from Damn Delicious.