Bring steaks to room temp: Take the steaks out of the fridge 20–30 minutes before cooking. Pat them very dry with paper towels. Season generously with salt and pepper on both sides.

Preheat the pan: Set a large heavy skillet (cast iron is best) over medium-high heat. Add 1 tablespoon oil and let it get hot until shimmering.

Sear the steaks: Place steaks in the hot pan without crowding. Sear for 2–4 minutes on the first side until a deep brown crust forms. Flip and sear another 2–4 minutes. Adjust time based on thickness and desired doneness.

Add butter and aromatics: Reduce heat slightly. Add 2 tablespoons butter, half the minced garlic, and the thyme (and rosemary, if using) to the pan. Tilt the pan and spoon the melted butter over the steaks for 30–60 seconds.

Check doneness: Aim for 125°F for rare, 130–135°F for medium-rare, or 140–145°F for medium. Use an instant-read thermometer for accuracy.

Rest the steaks: Transfer steaks to a plate and tent loosely with foil. Let them rest 5–8 minutes so the juices redistribute.

Cook the mushrooms: In the same pan, add the remaining 1 tablespoon oil and 1–2 tablespoons butter. Add the sliced mushrooms in a single layer. Cook undisturbed for 2–3 minutes to brown, then stir and cook another 3–4 minutes until tender and golden.

Add garlic and finish: Stir in the remaining garlic and cook 30 seconds until fragrant. Season with salt and pepper. If you like, add a small squeeze of lemon juice to brighten the richness.

Return juices to the pan: Pour any resting juices from the steak plate into the mushroom mixture and stir. Taste and adjust seasoning.

Serve: Slice the steaks against the grain. Spoon the garlic butter mushrooms over the top. Finish with chopped parsley and an extra pat of butter if you want it extra saucy.