Combine mustard, soy sauce, thyme, garlic and ginger. Rub meat (not bones) all over with mustard mixture and place in roasting pan.
Refrigerate covered 1 1/2 to 2 hours or overnight. Remove meat from refrigerator and let come to room temperature, approximately 1 hour.
Preheat oven to 450° F.
Stuff center of roast with prepared dressing. Insert meat thermometer between two ribs, without touching bones.
Reduce oven setting to 350° F and bake for 15 minutes per lbs or until thermometer registers 165° F (medium).
Transfer to meat platter and serve. Recipe in this section.
Cover crown bones with foil to prevent discoloration. Crumple a ball of aluminum foil and place in the center of the lamb to help keep the shape during baking.
Reduce oven setting to 350° F and bake 35 minutes per pound. When the roast has 1 more hour to bake, remove from oven and discard foil ball (not the foil on bones).
Stuff the center with prepared filling and return to 350° F oven for final hour of baking.
When done, transfer the roast to meat platter and remove foil from bones. Garnish roast by piercing a hole halfway through each tomato (use a small knife) then pushing a tomato onto each rib bone.Serves 6