In a mason jar or bowl, combine rolled oats and milk.
Add pumpkin puree and mix well.
Stir in pumpkin pie spice, maple syrup, and chia seeds.
Add vanilla extract and mix until fully combined.
Cover with a lid or plastic wrap.
Refrigerate overnight (or at least 4 hours).
In the morning, give the oats a good stir.
Taste and adjust sweetness if necessary.
Top with your choice of nuts, seeds, or dried fruits.
Enjoy cold or warm in the microwave for 30 seconds.