Directions

1. Heat 2 tablespoons of the oil in a large heavy skillet over medium-high heat. Add the mushrooms and cook, stirring occasionally, until soft and golden, about 7 minutes. Season with salt after they have turned golden. Transfer to a bowl; set aside.
2. Melt 1 1/2 tablespoons of butter with remaining 1 tablespoon oil in same skillet over medium heat. Season the steaks with salt and cracked pepper. Add steak, garlic, and thyme to skillet. Cook about 4 minutes per side for medium-rare. The steaks will be more rare than medium. If you like them more done, do them at least 5 minutes per side. Transfer to a plate and let rest while preparing sauce.
3. Discard the garlic and rosemary from skillet. Pour off all but 1 1/2 tablespoons of the fat. Add the wine; stirring up bits, until reduced to about 3/4 cup. Strain the reduction and return the liquid to the skillet. Stir in the stock and bring to a boil. Simmer until reduced to 3/4 cup or so, about 5 minutes. Remove from heat and add the remaining butter. Add the mushrooms back to the pan and season with salt and pepper.