Add the milk of your choice, Greek yogurt, maple syrup (or honey), vanilla extract, pumpkin pie spice, cinnamon, and pumpkin puree to a medium-sized bowl.
Stir well until everything is combined and smooth.
Add the chia seeds and oats.
Fold everything together until the oats are completely moistened.
Transfer into 4-5 small pint-sized jars (or airtight containers).
Place in the fridge and allow to soak for 2-4 hours before serving (or overnight for the best results).
Store in the refrigerator for up to 4-5 days.
To enjoy: remove from the fridge, stir, and then garnish with your choice of pepitas, chopped pecans, whipped cream, greek yogurt, and/or a pinch of pumpkin pie spice.
Notes
With protein powder: Add 1 scoop of your favorite Vanilla protein powder (or Cinnamon - I like Ghost Cinnabon Protein Powder) and mix it in at the same time you add the cashew milk.