1. Preheat the oven to 350 degrees and prepare an 11×17 baking sheet with parchment paper.
2. In a large bowl, combine the flour, baking soda, and salt. Mix well and set aside.
3. In a separate mixing bowl, cream together butter and sugars until smooth using an electric hand or stand mixer.
4. Add the pudding package and mix for another minute until fully combined.
5. Add the eggs and vanilla and continue to mix until smooth.
6. Add dry ingredients to the pudding mixture and blend until all ingredients are fully incorporated.
7. Using a rubber spatula, fold in the chocolate chips and M&M’s, mixing evenly.
8. Using a 1 inch cookie scoop, scoop each cookie compactly and roll in the palms of your hands, creating an even and round shape.
9. Place each cookie dough ball on the baking sheet, spacing about 2 inches apart. Repeat until the sheet is full.
10. Bake for 8-10 minutes.
11. When done, allow the cookie to cool on the baking sheet for about 1 minute before transferring to a cooling rack. Serve immediately or when completely cooled.