Christmas Monster Cookies are what you get when you combine all your favorite cookie recipes – chocolate chips cookies, M&M cookies, peanut butter cookies, and oatmeal cookies!
Preheat oven to 350 degrees and line baking sheets with parchment paper.
In a large bowl, cream butter, brown sugar, white sugar, and eggs until light and fluffy.
Add peanut butter and mix until combined.
Add baking soda, vanilla extract, and oats and stir until well combined.
Stir in mini chocolate chips and red and green M&Ms.
Using an ice cream scoop, scoop out rounded balls of dough onto the parchment paper lined baking sheet, leaving an inch of space between balls to allow room for the cookies to spread.
Bake for 15 to 18 minutes or until the cookies are golden brown and the center of the cookies are baked but still soft. The cookies will stiffen as they cool, resulting in a soft, chewy cookie.
Allow to cool on the baking sheet for a few minutes, then transfer your monster cookies to a cooling rack to cool completely.
Store in an air-tight container or freeze for future use.