In a ziploc bag, combine taco seasoning mix, olive oil, and 1/4 cup water. Seal bag and mix well. Add chicken pieces; turn to mix. Refrigerate 5 minutes or up to 12 hours.
Preheat oven to 350 degrees F.
In a medium bowl, combine 2-1/2 cups of the Monterey Jack cheese, cilantro, salt, ricotta cheese, chiles and egg. Mix well.
Heat large nonstick skillet over medium-high heat until hot. Add chicken with marinade. Cook and stir 5 to 10 minutes or until chicken is no longer pink in the center.
In an ungreased 9x13 inch glass baking dish, combine 1/2 cup of the salsa and 1/4 cup water. Mix well. Spread evenly in the bottom of the baking dish.
Spoon 1/3 cup of the cheese mixture down the center of each tortilla. Top with chicken. Roll up. Place filled tortillas, seam side down, over salsa mixture in baking dish. Drizzle enchiladas with remaining salsa. Sprinkle with remaining 1/2 cup cheese mixture.
Bake at 350 degrees F for 20 to 25 minutes or until cheese is melted.