Preheat the oven to 350 degrees Fahrenheit (175 degrees Celsius).
Line cookie sheets with parchment paper. If you don't have parchment paper, you can grease the cookie sheets instead.
In the bowl of your electric mixer, cream together the softened butter, brown sugar, sugar, peanut butter, and eggs until light and fluffy.
Add the baking soda, vanilla extract, and Gluten Free oats and mix on low speed until well combined.
Stir in the chocolate chips and M&M's.
Use a large cookie scoop to scoop rounded balls of dough and place them on the lined cookie sheets, leaving space between them for the cookies to spread. You can flatten the cookies slightly before baking if you prefer.
Bake the cookies for 12-15 minutes, or until they are lightly golden brown and don't look gooey in the center. They are better slightly undercooked than overcooked.
Let the cookies cool on the cookie sheet for a couple of minutes before moving them to a wire rack to cool completely.
I hope you enjoy these cookies! They are a favorite in my family.