In 2-quart saucepan, cook onion, garlic and water over medium heat 2 to 4 minutes, stirring occasionally, until onion is tender and water has evaporated.
Stir in tomatoes, chiles, salt, chili powder and ground red pepper. Cook about 2 minutes until hot, stirring occasionally.
Reduce heat to medium-low. Add cheeses; cook, stirring constantly, just until melted. Sprinkle with chili powder. Serve with cut-up fresh vegetables.