Jack gives you his mom's marinade recipe in Part 3 MY MOM IS GREAT SERIES.
Here is the recipe:
Beef short ribs and/or Beef back ribs
1 cup of soy sauce
(1/4 cup sugar if you use La Choy soy sauce / 1/3 cup sugar if you use Kikkoman's soy sauce)
1 tablespoon minced onions
1 tablespoon minced garlic
mix 4 ingredients to make marinade. Marinate meat for 40 minutes then grill. Enjoy!