Combine dry ingredients. In a medium bowl, combine oats, chia seeds, salt, cinnamon, and pumpkin pie spice. Mix together.
Add wet ingredients. Add the milk, yogurt, pumpkin, maple syrup, and vanilla extract. Stir all ingredients together until thoroughly combined.
Chill. Place oats in an airtight container (such as jars or airtight glass storage containers) and chill for at least 3-4 hours, ideally overnight.
Remove from fridge, top, eat. The next morning or when you're ready to eat, fetch your oats from the fridge and top with nuts, seeds, yogurt, or whipped cream.
Notes
Cook time. This recipe reflects hands-on time only, which is 10 minutes. It will actually be at least 3-4 hours (ideally overnight) before oats are ready to be eaten.
Chilling the oats. Sometimes I like to make the oats directly in the container I plan to chill them in. That way you only need dirty up one bowl!
Vegan version. I love overnight oats because you can easily make them vegan! Simply be sure to use a plant-based yogurt and milk instead of dairy.