Preheat oven to 350. Sprinkle taco seasoning over chicken, drizzle with olive oil and bake until juices run clear, about 15 minutes. Shred the chicken with a fork.
Place a single layer of tortilla chips on a foil lined tray, top with chicken and green chiles and heat in the oven for 5 minutes. Remove and top with cheese sauce, avocado and cilantro. Serve immediately with lime wedges.
In a medium saucepan over medium heat, melt the butter. Whisk in the flour and cook for 1 minute. Slowly whisk in the milk and stir until the sauce is thick and creamy. If the sauce is too thick, add more milk to thin it out. (You are looking for an egg nog consistency).Reduce the heat to low and stir in the salt, cumin and cheeses. Stir until the cheese is melted. Remove from heat.
You will probably have leftover cheese sauce. You can store it in the fridge for a couple of days. Heat it up slowly over low heat and use it to top a baked potato, steamed broccoli, or throw in some cooked pasta for a quick mac-n-cheese!