Most vegetables need to be reconstituted and cooked prior to eating. There are a few exceptions like potatoes and zucchini. The best way to reconstitute most vegetables is to do it in two steps. The first is to place the vegetables in a container and pour in an equal amount of water or other liquid. Hot or boiling liquid will shorten the time, but it will begin to cook the food. Cold liquid works fine but takes longer. The soak time depends on the size and thickness of the pieces. It can take anywhere from 10 minutes to 2 hours. Do not soak vegetables for longer than 2 hours or this can result in the growth of bacteria.
The second step is the cooking process. While it is possible to do this in one-step, your vegetables will be more flavorful and tender if you do it in two steps. The exceptions are leafy vegetables like cabbage, lettuce and spinach. These should be cooked and rehydrated in one-step.
The finished rehydrated vegetables should be near their fresh size.