Combine cooked chicken, chopped onion and softened cream cheese in bowl.
Heat enchilada sauce in skillet on low (I used the one I cooked the chicken in)
Dip one tortilla at a time in enchilada sauce (so it doesn't crack or break), shake off excess sauce in skillet, place a heaping tablespoon of filling on one side of tortilla and roll up. Place seam side down in 13 x 9 baking dish.
After all of the enchiladas are in the baking dish, pour the remaining enchilada sauce over the top and sprinkle with shredded cheese. NOTE: My daughter prefers to put thin slices of Velveta cheese on top rather than the shredded cheese.
Bake in preheated 350 degree oven for 20 minutes or until sauce is bubbly and cheese has melted.