Pat steaks dry with paper towels and season well all over with salt and pepper.
In a large cast iron skillet or large stainless steel skillet, heat 1 tablespoon butter and olive oil over medium-high heat until pan is hot.
Add steaks to pan and arrange smashed garlic cloves and thyme sprigs around steaks. Cook steak 3-5 minutes on first side until a deep golden brown, then flip to opposite side and add remaining 1 tablespoon butter.
Cook steak an additional 2-4 minutes on second side, using a spoon to baste steak occasionally with butter, until steak reaches your desired doneness. (130F for medium rare, 140F for medium, 150F for medium well, 160F for well done*)
Remove steak from pan to a plate and cover with foil to keep warm. Set aside. Remove garlic and thyme sprigs from pan and discard.
Keep pan over medium-high heat. Add mushrooms to pan and saute in pan drippings 3-5 minutes until just tender. Transfer mushrooms to a bowl and set aside.
Wipe pan clean from drippings and pour balsamic vinegar and honey into pan. Bring to a simmer over medium-high heat, then reduce heat to medium-low and let simmer 5-8 minutes until glaze is slightly reduced and thickened.
Remove pan from heat and add steak and mushrooms back to pan, spooning glaze over top. Garnish skillet with extra thyme and serve immediately while hot. Enjoy!