Beat together the butter, brown sugar and granulated sugar until combined. Add the peanut butter to the mixture and beat until combined. Beat in the eggs and vanilla extract.
Add the flour, baking powder and baking soda and slowly beat until a dough forms. Add the oats and fold together until combined. Add the chocolate chips and M&Ms and fold together until fully incorporated.
Chill the dough for one to two hours then roll into dough balls. Space the cookies 3-4 inches apart on a baking sheet lined with parchment paper.
Bake for 15 minutes at 375 degrees Fahrenheit. Let cool on the pan slightly then enjoy!