In a dry, hot skillet, toast chiles over medium-high heat until pliable, 3 to 5 minutes; turn often to prevent burning. Remove seeds and veins from chiles, and discard. Soak each type of chile separately in enough hot, salted water to cover for about 20 minutes. Drain, and reserve liquid.
Grind marjoram, cumin seeds, oregano, bay leaf, thyme, and cloves in a spice grinder.
In batches, combine drained chiles, ground herbs, garlic, vinegar, 1/2 cup soaking liquid, and 2 teaspoons salt in a blender. Transfer to a large bowl. Add chicken, and marinate for at least 1 hour, preferably overnight, refrigerated.
Cut 3 (16 by 16-inch) parchment-paper squares. Place a drumstick, thigh, and an avocado leaf in the center of each square. Bring the 4 corners together, and tie with string. Place in a steamer, and steam over simmering water for 1 hour.
To serve, remove string, and open parchment paper, folding under slightly. Serve with fresh, warm tortillas.
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