In a large bowl, combine cumin, chili powder, lime juice, garlic, and 1 tsp olive oil. Marinate chicken pieces in this marinade for 20 minutes. In heavy skillet, heat remaining olive oil. Brown chicken pieces on all sides. Add marinade, tequila, and water. Cook for approximately 10 minutes. Transfer chicken pieces to a platter. Reduce sauce over high heat until it thickens to a good coating consistency, pour over chicken, and serve garnished with cilantro.