In a small bowl, mix together tamari, shallots, ginger, and garlic. Place steak in a large bowl and cover with tamari mixture. Cover tightly and refrigerate. Allow to marinate for as long as possible, up to 48 hours (but can be as few as 1 hour).

Preheat grill to medium high heat. Place steaks on grill and cook for approximately 10 minutes per side for medium rare steaks. Internal temperature should be between 130-140 degrees for medium rare steaks.

Once cooked to desired doneness, remove steak from grill and let sit for 5 minutes. Remember,t he steak will continue to cook until it's sliced, so take this into consideration with cooking time and desired doneness.

Slice steak against the grain and serve immediately.