• Heat the oven to 350℉ and line a 9x13 baking pan with parchment paper. If you do not want to remove the cookies from the pan then light spray the bottom with cookie spray or grease with butter.
• Add the butter, granulated sugar and brown sugar to a large mixing bowl, and using a hand mixer on medium speed, cream together until light and fluffy. You can do this with a stand mixer as well.
• Add the eggs, salt and vanilla, then mix on medium speed until combined.
• Add one cup of the flour, the baking soda and baking powder to the wet ingredients and mix on low to combine. Then add the rest of the flour and mix on medium speed until the flour is incorporated. Scrape the side of the bowl and mix quickly to get everything mixed in.
• With a wooden spoon, stir in the chocolate chips, M&M's and sprinkles. If you are using a stand mixer, you can mix this in on a very low speed, being careful not to break up the M&M's.

  Optional - hold out some extra M&Ms and sprinkles for the top of the dough.
• Press the cookie dough into the prepared baking pan in an even layer. Add additional M&Ms or sprinkles on top if desired.
• Bake for 30-35 minutes or until a toothpick inserted in the center comes out mostly clean.
• Let the cookies cool on a wire rack before cutting them into squares and serving. Enjoy!

Storage

• These cookies will keep in an airtight container for up to four days.
• You can freeze the baked cookies once completely cooled in an airtight freezer container. Stack the cookies with wax paper or parchment paper between the layers. Let thaw on the countertop before eating.