In bowl of food processor or jar of a blender purée all sauce ingredients until smooth. Pour into a 2 quart sauté pan, simmer sauce, stirring, 3 minutes and season with salt and pepper, if desired. Keep warm. (Sauce may be made 2 days ahead and chilled, covered.) Yield 6 cups.
Cook turkey sausage as specified on the package. Always cook to well-done, 165°F as measured by a meat thermometer. Set aside.
Assemble Chilaquiles in shallow dishes or soup bowls. Crumble 6 tortilla chips into each bowl. Top with ¾ cup very hot sauce. Sprinkle with ¼ cup turkey sausage crumbles. Garnish with onion, feta cheese, cilantro and avocado, if desired.