Saute chicken, onion and chili powder in butter. Drain and set aside. Mix soup, sour cream, chilies and jalapenos in a bowl. Spray the casserole dish with cooking spray. Spread 1 Cup soup mixture on bottom of dish. Spoon to cups of Chicken mixture, 3 Tablespoons soup mixture and some of the cheese down the center of tortilla. Roll and place seam side down in dish. Repeat until full. Top with remaining soup and cheese. Bake uncovered at 325(F) for 45 min.