Hoisin sauce is available at Asian markets and in the Asian section of some supermarkets.
Directions
Heat oil in heavy large nonstick skillet over medium-high heat. Add garlic and ginger and stir until fragrant, about 1 minute. Add eggplant and mushrooms and sauté 2 minutes, stirring to coat with seasonings. Add next 4 ingredients and cover. Simmer until eggplant is tender, stirring occasionally, about 10 minutes. Uncover and cook until sauce is absorbed and mixture is thick, about 2 minutes. Season to taste with salt.
Arrange lettuce leaves around edge of platter. Spoon eggplant mixture into center. Spoon eggplant mixture into center. Spoon some eggplant mixture into each lettuce leaf. Garnish generously with chopped green onion, bell pepper and jicama. Fold up sides of lettuce as for a taco and serve.