Marinade: Combine marinade ingredients.
Makes enough for 2 pounds of beef.
To use: Toss paper-thin slices (1 inch by 3 to 4 inches) of beef sirloin with the marinade in a nonmetallic bowl. Refrigerate 6 to 8 hours or overnight. Drain meat, reserving 3/4 cup of the marinade. Thread meat on bamboo skewers.
Sauce: Remove and discard seeds from pasilla chile. Coarsely chop chile and cover with boiling water. Soak for 20 to 30 minutes. Drain, and put in a food processor with achiote paste and olive oil. Puree. Add the 3/4 cup marinade and blend until smooth.
To use: Brush on skewers of meat. Broil or grill until meat is done, about 5 minutes, basting with marinade several times. Brush again before serving.
Adapted from Time-Life's "Cooking of Latin America."
From an article by Heidi Haughy Cusik, The San Francisco Chronicle, 7/1/92.