These bars are perfect for a large group and chewy delicious. Great for a party!
Heat your oven to 325 degrees. Line a half-sheet (12x17) with parchment paper or spray with cooking spray.
Melt the butter in a large glass bowl in the micorwave. Add the brown sugar and white sugar and stir together. Then add the eggs and egg yolks and vanilla. Wisk it together until blened.
In another bowl, mix the flour, salt and soda together. Add the flour mixture to the wet ingredients and stir until a few streaks are left (don't overmix).
Stir in the chocoalte chips and/or M&M's. Press the dough into the prepared pan.
Bake for 22-25 minutes or until the edges are lightly golden. Don't overbake or they will be dry. Let them cool before cutting into bars.