How to Make It
In a medium saucepan, combine all of the marinade ingredients and bring just to a boil, stirring to dissolve the sugar. Let cool completely. Transfer the marinade to a large, sturdy resealable plastic bag.
Add the short ribs to the marinade and seal the bag. Set the bag in a baking dish and refrigerate overnight. Bring the short ribs to room temperature before cooking.
Light a grill and brush with oil. Remove the ribs from the bag and discard the marinade. Working in batches, grill the short ribs over high heat, turning once, until nicely browned and charred in spots, about 2 minutes per side. Transfer the ribs to a platter and serve with lemon wedges.
Flanken-cut short ribs are cut across the bone, so they appear to have a row of small bones dotting a thick strip of meat.