Preheat your oven to 350 degrees. Line rimmed baking sheets with parchment paper. Set aside. In a medium sized bowl, mix together the flour, baking soda, baking powder, and salt until fully combined. Set aside.
1 cup all purpose flour, 1/2 teaspoon baking soda, 1/2 teaspoon baking powder, 1/4 teaspoon salt
In a large bowl, beat together the butter, brown sugar, and granulated sugar until light and fluffy, about three minutes. Then proceed to beat in the peanut butter until fully combined.
1 cup unsalted butter, 1 cup brown sugar, 1/2 cup granulated sugar, 1 1/2 cups creamy peanut butter
Then beat the eggs, one at a time, into the butter and sugar mixture. Finally, beat in the vanilla.
2 large eggs, 2 teaspoons vanilla extract
Add in the flour mixture all at once (see note 2) mixing it in on a very low speed until you have no risk of flying flour, and then up the speed just a little and mix in until the flour has just disappeared.
Finally, stir in the chocolate chips, M&M's, and oats.
1 cup chocolate chips, 1 cup M&M's, 1 cup quick cooking oats
Use a 1 1/2 tablespoon cookie scoop to make uniformly sized cookie balls. (Or make one inch sized dough balls.) Place them two inches apart on the cookie sheets and bake for 10 to 12 minutes or until they are golden brown, rotating halfway through.
Remove from the oven. Allow to cool on the baking sheets for two minutes, then transfer to a wire rack to cool completely. Once completely cooled, transfer to an airtight container and store for up to one week.