Preheat oven to 400°F. Mix rosemary, 1 teaspoon of the sea salt, garlic powder, pepper and thyme in small bowl. Coat steaks with seasoning mixture. Heat cast iron skillet on high heat until hot. Add oil; reduce heat to medium. Sear steaks 1 to 2 minutes per side or until browned. Remove steaks from skillet to plate. Do not cover.
Stir sweet potatoes, shallots and remaining 1/2 teaspoon sea salt into skillet. Cook and stir 8 to 10 minutes or until tender. Add red wine; cook 1 minute, stirring to release browned bits from bottom of pan. Add mushrooms and asparagus; cook and stir 2 minutes. Place steaks on top of vegetables.
Transfer skillet to oven. Roast until steaks are desired doneness. For medium-rare doneness, roast 4 to 5 minutes or until meat thermometer inserted into center of steak reaches 130°F to 135°F. For medium doneness, roast 7 minutes or until steak are 140°F to 145°F. Let steaks stand 5 minutes before slicing. Serve with vegetables.