Combine the rolled oats, pumpkin puree, milk, cinnamon, nutmeg, allspice, salt, and maple syrup in a mixing bowl. Stir thoroughly until the mixture is smooth and the oats are evenly coated with the spices and pumpkin.
Pour the mixture into a jar or container with a lid, making sure everything is evenly distributed. Seal tightly to prevent spills and ensure even soaking.
Place the jar in the refrigerator and let it soak overnight or for at least 6 hours. This allows the oats to absorb the flavors and become tender, with a creamy yet chunky texture.
Remove the jar from the fridge the next morning. Give the oats a gentle stir to incorporate any separated liquids and check the consistency.
Scoop the pumpkin spice overnight oats into bowls. The mixture should be creamy with visible oats and a smooth, thick texture. Garnish with your favorite toppings like chopped nuts, seeds, or a drizzle of additional maple syrup if desired.
Enjoy your cozy, flavorful breakfast—a perfect balance of spice, pumpkin, and creamy oats ready to start your day with fall-inspired warmth.