Separate tender or leafy vegetables from all other vegetables, such as root or seed vegetables. Examples of the first category include tomatoes, chard and spinach. Examples of the latter category include corn, carrots and peas. Hydrate these two groups of vegetables separately.
Place vegetables from the second category in a bowl and cover them with cold water.
Allow them to soak for 30 to 90 minutes.
Pour the vegetables and the water they soaked in into a large pot. Simmer them on medium heat until they become tender.
Fill another pot about half full of water and heat it until it simmers.
Add vegetables from the first category to the pot of water and simmer them until they become tender. You do not need to presoak these vegetables.
Separate large and small pieces of dehydrated food. They require different lengths of time to reconstitute. If you have both root vegetables and leafy vegetables, such as carrots and spinach, separate these into different piles.
Place each category of dehydrated food into its own bowl.
Add enough cold water to each bowl to generously cover the food.
Place the bowls in the refrigerator.
Allow dried vegetables to soak for about two hours. The exact length of time will vary, depending on the size and type of food. Root vegetables and large pieces of food may require more time. Let the food soak longer if it is not yet tender.