Combine garlic, thyme and pepper; press onto beef steaks. Place steaks on grill over medium, ash-covered coals. Grill, uncovered, 13 to 15 minutes for medium rare to medium doneness, turning occasionally. Season with salt. (Or to broil, place steaks on rack in broiler pan so surface of beef is 2" to 3" from heat. Broil 13 to 16 minutes for medium rare to medium doneness, turning once.)
Mix horseradish cream ingredients. Serve with steaks.