Prep the steak: Pat dry and season generously on both sides with salt and pepper. Let it sit at room temperature for 20–30 minutes. This helps it cook evenly.

Heat the pan: Place a large skillet (cast iron is ideal) over medium-high heat. Add 1 tablespoon olive oil and 1 tablespoon butter. When shimmering and just starting to smoke, you’re ready.

Sear the steak: Lay the steak in the pan and don’t move it for 3–4 minutes. Flip and sear the other side for 3–4 minutes for medium-rare, adjusting time to your preference. Add a small knob of butter and baste if you like.

Rest the steak: Transfer to a plate and tent loosely with foil. Rest for 8–10 minutes. Resting keeps it juicy.

Sauté the mushrooms: In the same pan, add another tablespoon of butter. Toss in the mushrooms with a pinch of salt. Cook undisturbed for 3 minutes to brown, then stir and cook 3–4 minutes more until golden.

Add garlic and herbs: Lower heat to medium. Add minced garlic and a sprinkle of thyme. Stir for 30–45 seconds until fragrant. Don’t let the garlic brown too much.

Deglaze and simmer: Pour in the broth to lift the browned bits. Add lemon zest and a small squeeze of juice. Simmer 2–3 minutes to reduce slightly. For extra richness, add a splash of cream now.

Finish with Parmesan: Stir in most of the grated Parmesan until it melts into the sauce. Taste and adjust with salt, pepper, and lemon as needed. Add red pepper flakes if you like a little heat.

Slice the steak: Slice against the grain into 1/2-inch strips. Return to the pan or plate the steak and spoon the mushroom-Parmesan sauce over the top. Sprinkle with fresh parsley and the remaining Parmesan.

Serve: Great with mashed potatoes, polenta, buttered noodles, or crusty bread to catch the sauce.