Heat oven to 375F. Cook and drain noodles as directed on package.
Cook beef, onion, cilantro and red chilies in 10-inch skillet over medium heat 8 to 10 minutes, stirring occasionally, until beef is brown; drain.
Place 5 of the noodles in bottom of ungreased rectangular baking dish, 13x9x2 inches.
Layer with 1 1/2 cups of the beef mixture, 1 cup of the ricotta cheese and 1 1/4 cups of the salsa. Repeat with remaining noodles, beef mixture, ricotta cheese and salsa.