This is my favorite, favorite chicken enchilada recipe. It's very quick and easy and people are always asking for the recipe. It's from The Junior League of Spokane's Gold'n Delicious cookbook (one of the best cookbooks ever!).
Melt butter in a large skillet over medium heat. Add onion and saute until tender, about 3 minutes. Stir in chicken, 1/2 cup of picante sauce, cream cheese and cumin. Cook until thoroughly heated. Add 1 cup cheese and remove from heat.
Spoon 1 cup picante sauce on the bottom of a greased 9 x 12" baking dish. Spoon approximately 1/4 cup chicken mixture into the center of each tortilla, roll and place seam-side down in pan. Top with remaining picante sauce and cheese.
Cover with foil and bake at 325 for 20 minutes. Remove foil and bake for an additional 10 minutes.