Christmas M&M Cookie Bars

0 Preheat the oven to 350°F. Spray a 9”x13” baking pan with nonstick baking spray, and set aside. You may also line it with parchment paper to assist in lifting out the final bars.
1 In the bowl of a stand mixer using the flat beater attachment, cream the softened butter, granulated sugar and brown sugar together until the butter is light yellow and the sugars are well incorporated, about 2-3 minutes. Use a rubber spatula to scrape down the sides.
2 Add in the egg and vanilla extract, beating until combined, about 1-2 minutes. Scrape down the sides using the rubber spatula to ensure all ingredients get mixed in.
3 Measure the flour, salt and soda into the mixing bowl before turning on the mixer at a low speed. Continue mixing until the batter has come together and is nice and sticky.
4 Measure in the M&M candies, chocolate chips and sprinkles. Gently mix them into the batter using the flat beater attachment or a rubber spatula.
5 Scoop the cookie dough out of the bowl and into the prepared baking pan. Use your hands or an offset spatula to press the batter out evenly throughout the pan.
6 Bake for 30 minutes, or until golden brown and cooked through.
7 Let cool completely on a wire cooling rack before cutting into 24 cookie squares.
8 Enjoy with a glass of your favorite kind of milk!