Remove the filet from the refrigerator 30 to 45 minutes before cooking to bring it to room temperature. Season generously with kosher salt on all sides right before it goes into the pan. The pepper goes on at the end.

Heat a cast iron skillet over high heat until smoking.

Add the olive oil, then place the filet in the pan. Sear without moving for 2–3 minutes until a deep crust forms. You'll know it's ready to flip once it releases from the pan. It sticks because the crust is still forming, so don't nudge it around if it's not releasing. The protein will almost always tell you when it's ready.

Flip the filet. Add the butter and thyme to the pan.

Baste the filet with the foaming butter for 1–2 minutes, tilting the pan to pool the butter and spooning it continuously over the top. Keep that frying sound going so you don't lose temperature.

Remove the filet when it reaches 120°F internal for medium-rare. Rest on a cutting board for 5 minutes. Carryover is the term for when the temperature keeps climbing after something is removed from the pan, which is why you pull a protein below its target and not at it. The multi-sear and rest method builds crust slowly while keeping the inside perfectly even, with no grey band and no overcooked edge.

In a wide shallow bowl, combine the arugula, parsley, chives, and dill.

Drizzle with olive oil and lemon juice. Toss gently, just enough to barely coat.

Season with flaky salt.

Slice the rested filet against the grain into ½-inch thick pieces.

Lay the slices over the herb salad while the steak is still warm. The greens will wilt slightly underneath.

Scatter shaved parmesan over the top.

Finish with a drizzle of olive oil and a pinch of flaky salt.