Snap off tough ends of asparagus. Cook asparagus in boiling water for 2 minutes or until crisp-tender. Drain well, and chill.
Combine soy sauce and next 4 ingredients (soy sauce through garlic), reserving 1/3 cup soy sauce mixture. Set aside. Place remaining soy sauce mixture, asparagus, and steak in a zip-top plastic bag; seal. Marinate in refrigerator 1 hour, turning occasionally.
Remove asparagus and steak from bag, and discard marinade. Place a grill pan over medium-high heat until hot. Add asparagus and steak, and cook steak 3 minutes on each side or until desired degree of doneness, turning asparagus as needed. Place steak on a platter, and cover with foil. Let stand for 5 minutes. Cut steak diagonally across grain into thin slices.
Combine 1/3 cup reserved soy sauce mixture, spinach, rice, celery, oil, and onions; toss to coat. Divide asparagus, steak, and wild-rice pilaf evenly among 4 plates.