Combine the lima beans and garlic, with broth or water to cover and simmer, covered, over low heat, for 15 minutes or until really tender (add more liquid if it is evaporating too quickly).
Puree lima beans in a food processor with grated orange rind and butter. For a finer puree, pass the lima beans through a sieve or food mill to remove skins; season to taste with salt and pepper.
Can be made in advance and reheated in microwave oven or double boiler.
Recipe Courtesy of Michelle Urvater