Preheat oven to 350
Line a 9 x 13 pan with foil and then spray with baking spray.
Combine butter and sugars. Beat until fluffy
Add in eggs and vanilla
Gradually add in flour and salt until blended.
Mix in chips and M & M
Spread batter into pan and bake for 20-25 minutes or until golden brown and a tooth pick comes out only slightly gooey.
Cool and remove from pan by lifting up the foil.