I have loads of bean dip recipes that rehydrate using cold water. If you are willing to get into dehydrating foods let me know and I can post a bunch of recipes. Here's a link to one of my hummus recipes and the link to an eggplant one that illustrates that it doesn't just have to be beans to be UL.
The Easiest of Trail Lunches (I chose to post this one because it shows the dried product for reference)
Roasted Eggplant Spread
and a black bean dip...
Black Bean Dip
© 2008 A Fork in the Trail
Dehydration Time: 5–7 hours
Makes 2–4 servings
Black beans are also known as black turtle beans and have an earthy flavor. They are a good source of protein and fibre.
1 19-ounce can black beans, drained and rinsed
2 cloves garlic, minced
1 1/2 tablespoons onions, minced
1/2 tablespoon olive oil
1 1/2 tablespoons salsa
1/2 teaspoon black pepper, freshly ground
2 1/2 teaspoons lime juice
3/4 teaspoon cumin
1 teaspoon cilantro, chopped
Pinch of salt
Purée the black beans, garlic, onions, olive oil, salsa, and lime juice. Add the black pepper, lime juice, cumin, cilantro, and salt and purée again. Dehydrate the purée on a lined dehydrator tray as you would for fruit leather. The dip will take between 5 and 7 hours to dry. Once it is dry, you can grind it into a powder (a spice or coffee grinder works best for this).
Rehydrate the bean dip using a formula of 1 1/2 parts dried mix to 1 part water. Wait 5 to 10 minutes and then add a little more water if necessary. Serve the hummus warm or cold with crackers, Greek pita wedges, or tortilla chips or as a spread in a chicken wrap.