Mix together soy sauce and garlic in a large resealable plastic food storage bag. Add scallops and marinate for 15 minutes at room temperature. Pat scallops dry and reserve marinade.
Heat oil in a large nonstick skillet. Sauté scallops for 2 minutes per side. Remove to a plate.
Mix together marinade, marmalade, orange juice, hoisin sauce and red-pepper flakes. Add to skillet and simmer on medium for 4 to 5 minutes until thickened. Add scallops and scallions and heat through.
While sauce is simmering, cook rice noodles following package directions. Add spinach during the last 2 minutes.
Serve scallops and sauce over noodles. Makes 4 servings.