Mexican Tortilla Soup

Heat oil in cooker, then add onions and garlic cloves. Saute until deep golden brown. Remove from cooker and puree with tomatoes in blender or food processor until smooth. Return to cooker and add broth. Heat to boiling. Bring up to high pressure, reduce heat and cook 10 minutes. Release pressure and remove the lid. Add cilantro and salt to taste. Place cheese and tortilla chips in individual soup bowls and pour hot soup on top. Serve with lime wedges, if desired.