Preheat oven to 375 F. Line a cookie sheet with parchment paper or silplat mat.
Combine flour, baking powder, baking soda and salt in medium bowl; set aside.
Add butter, sugar and brown sugar to a large mixing bowl or stand mixer and beat well until creamed together.
Add egg and vanilla and mix until combined.
Gradually mix in the flour and mix until combined.
Stir in chocolate chips and m&m’s.
Scoop dough into large balls (about 3 Tablespoons) and place on prepared baking sheet about 2 inches apart.
Bake for 8 to 10 minutes or until light golden brown around the edges (Do not over bake.)
Let stand 1 minute on cookie sheet, then transfer to cooling rack to cool completely
