Heat oven to 350*F. In small mixing bowl, combine cheese and 1 teaspoon of chili powder. Reserve 1/2 cup mixture. Set aside. In shallow dish, combine remaining 1/2 teaspoon chili powder, the tomato sauce, sugar, cumin, garlic powder, and cayenne.
Dip both sides of 1 tortilla in sauce. Sprinkle 1/4 cup cheese mixture down center of tortilla. Place 1 strip of chili and 1 tablespoon onions over cheese mixture. Roll up tortilla. Place seam-side-down in 11 x 7-inch baking dish. Repeat with remaining tortillas, sauce, cheese mixture, chili strips and 5 tablespoons onions.
Spoon remaining sauce over enchiladas. Sprinkle with reserved cheese mixture. Cover dish with foil. Bake for 23-28 minutes, or until sauce is bubbly and cheese is melted. Sprinkle each serving with 1 tablespoon tomato, 1 tablespoon sour cream and 1 teaspoon remaining onions.