In a bowl, combine the softened butter, Dijon mustard, capers, anchovy, shallot, garlic, parsley, thyme, rosemary, smoked paprika, curry powder, lemon zest, and a pinch of flaky salt.

Mix vigorously with a fork until everything is thoroughly combined and the butter is uniform in colour.

Spoon the butter onto a sheet of plastic wrap, roll it into a log about 4cm in diameter, and twist the ends tightly to seal.

Refrigerate for at least 30 minutes to firm up. (The butter keeps for up to 1 week in the fridge or 3 months frozen.)

Cut the potatoes into batons roughly 1cm x 1cm thick and as long as the potato allows. Try to keep them uniform for even cooking.

Rinse the cut potatoes in cold water until the water runs clear, then pat them completely dry with a clean tea towel. Moisture is the enemy of a crispy frite.

Heat the oil in a large, deep saucepan or deep fryer to 150°C.

Working in batches, fry the potatoes for 5–6 minutes — they should be cooked through but with very little colour. You're par-cooking them here.

Remove with a spider or slotted spoon onto a wire rack or paper towels. Spread them out and allow to cool completely. (They can sit at room temperature for up to 2 hours at this point.)

Remove the steaks from the fridge 30 minutes before cooking to take the chill off.

Pat the steaks very dry with paper towels — this is critical for a great sear. Season generously on both sides with flaky salt and cracked black pepper right before cooking.

Heat a heavy-based cast iron or stainless steel skillet over high heat until it is smoking hot. Add the neutral oil.

Lay the steaks away from you into the pan. Sear without moving for 2–2.5 minutes until a deep brown crust forms. Flip and sear the other side for another 2 minutes.

Reduce the heat to medium. Add the butter, garlic cloves, and thyme sprigs to the pan.

As the butter foams, tilt the pan and use a spoon to continuously baste the steaks with the hot butter for 60–90 seconds. This is the French technique of 'arroser' — it builds flavour and colour.

For medium-rare, pull the steaks when an instant-read thermometer reads 52–54°C (the steak will carry-over cook while resting).

Transfer the steaks to a wire rack and rest for 5–6 minutes. Do not skip the rest — it's essential for juicy meat.

While the steaks rest, increase the oil temperature to 190°C.

Fry the blanched potatoes in batches for 2–3 minutes until deeply golden and shatteringly crispy.

Remove immediately onto paper towels, season generously with fine salt, and serve right away — frites wait for no one.

Slice the Café de Paris butter log into 1cm rounds.

Place each rested steak on a warm plate. Top immediately with 1–2 rounds of Café de Paris butter so it begins to melt over the meat.

Pile the frites alongside. Serve at once with a