1. Stir together the soft bread crumbs, onion, water, sugar, soy sauce, garlic, and ground ginger in a large mixing bowl. Add the ground beef and mix well. Shape the meat mixture into six 3/4-inch-thick patties.
2. For a charcoal grill, place patties on the grill rack directly over medium coals. Grill, uncovered, for 15 to 18 minutes or until an instant-read thermometer inserted into the side of a patty registers 160 degreesF, turning once.
3. For a gas grill, preheat grill. Reduce heat to medium. Place patties on the grill rack; cover and grill as above.
4. Serve burgers in buns topped, if desired, with sliced cucumbers and lettuce. Makes 6 servings.
Test Kitchen Tip: When grilling, to test for medium heat, you should be able to hold your hand over the heat at the height the food will cook for 4 seconds before having to pull your hand away.