Preheat the oven to 350 F. In a medium bowl, whisk together flour, oats, salt, and baking soda. In a large bowl, combine butter with peanut butter, brown sugar, and granulated sugar. Mix until fluffy.
Add in the egg and vanilla extract, and mix until smooth. Add in the flour mixture, mix until it is fully combined. Fold in the sprinkles, chocolate chips, and M&Ms.
Roll the cookie dough into balls and place the cookies onto a large ungreased baking sheet at least 2-inches apart. Bake for 10-12 minutes.
