Add all ingredients to a large mason jar and seal with lid. If you think the soaked nuts and raisins might be a textural issue for you, you can wait to mix these in after the chia seeds have expanded overnight. Shake vigorously for several minutes until all chia seeds are suspended and the pumpkin puree is fully mixed in.
Store in the fridge for at least one hour or overnight, shaking occasionally to prevent the chia seeds from settling on bottom. Serve immediately or store in the fridge for several days.
Notes
You can add more chia seeds or more liquid to make the pudding more or less thick.
This recipe about 3.5 cups, so you will need a jar with a capacity of 32 ounces to allow room to agitate the chia seeds. Alternatively, you can use two jars with a volume of 16 ounces or greater (dividing the ingredients equally between the jars).
If you don't have a jar you can whisk the ingredients in a bowl, but be sure to whisk until the chia seeds are fully suspended.
Mix or shake up the chia seeds at least several times during their resting period. This will help prevent them from turning into a brick at the bottom of the jar.
After the pudding is made, try dividing it into smaller individual mason jars for a simple meal prep or grab-and-go snack.
If you want your nuts to be crunchy, add them prior to eating.
Storage: Store chia pudding in an airtight container or sealed jar in the fridge for up to 1 week.Yields about 3.5 cups.