Preheat oven to 350°F. Line a baking sheet with parchment paper.
In a large bowl, cream together the peanut butter, butter, and sugars using a hand mixer until light and fluffy, about 1–2 minutes.
Add the almond milk, egg and vanilla; beat until just combined.
Add rolled oats, oat flour, baking soda and salt to wet ingredients. Stir together with a spatula or on low speed until everything is well mixed.
Stir in the M&M’s and chocolate chips.
Using a cookie scoop or tablespoon scoop dough into balls (about 1.5 Tbsp). Place on prepared baking sheet, and gently flatten slightly. You don’t want to flatten too much because the cookies will spread.
Bake for 9–11 minutes, or until the edges are golden and centers are set but still soft.
Let cool on the pan for 5 minutes before transferring to a wire rack to cool completely.
Notes
Storage: Keep these cookies in an airtight container on the counter for 3 to 4 days or store them in the fridge for up to a week. They also freeze well. Place parchment between layers so they do not stick together and let them sit on the counter before enjoying.