Lettuce leaves * or you substitute 2 whole chili peppers, crushed. In a pot, poach the chicken breasts in a little boiling water for 10 minutes until white and opaque. In a dry frying pan, toast the Szechuan peppercorns over moderate heat, then crust or grind them; set aside. Remove the chicken breasts from the pot, drain and cool them. Slice them, then shred the slices into julienne pieces. In a mixing bowl, combine the sesame paste and green tea (or the peanut butter and sesame oil -See NOTE). Add the vinegar and soy sauce; blend well. Add the peanut oil, red pepper, ginger, scallion, garlic, sherry, cayenne pepper, and the peppercorns. Mix all ingredients very well. Toss the chicken strips in this sauce, to coat. Refrigerate until 20 minutes before serving. Pass the chicken and the lettuce leaves separately, and let each guest place a small portion of the chicken in the middle of a lettuce leaf and roll it up like an egg roll to eat using fingers. Makes 6 appetizer servings. NOTE: The authentic recipe calls for green tea to thin the sesame seed paste, but you may substitute chicken broth, or simply water, if you prefer. Another substitution you may make if you wish is peanut butter for the sesame seed paste along with sesame oil instead of green tea. This dish is served cold or at room temperature and can be made a day ahead . -Verdi