Saute the beef (or turkey) on medium heat until browned.
Drain the fat, and add the simmer sauce. Stir thoroughly.
Turn heat to low, cover, and let simmer for 5 minutes.
Wash and dry romaine leaves, slice onion, and shred cheese (optional).
Alternatively, chop lettuce and mix in with onion and cheese for a salad.
Scoop meat into romaine "shells", and top with salsa, onion, and cheddar.
If you're making a salad, mix the salad ingredients into a bowl and top with the meat. Use salsa as salad dressing.