Reverse-Seared Tomahawk with Rosemary-Garlic Butter

Ingredients

• 1.3kg tomahawk ribeye, bone in (about 5cm thick)
• 2 tbsp coarse sea salt
• 2 tbsp coarsely cracked black pepper
• 1 tbsp neutral oil (for the sear)
• 100g salted butter
• 4 garlic cloves, lightly crushed but whole
• 3 sprigs rosemary
• 2 sprigs thyme
• flaky sea salt, to finish
• 2 bunches spring onions, trimmed
• 1 lemon, halved
• 1 tbsp olive oil
• flaky sea salt and black pepper
• 2 banana shallots, finely diced
• 200ml dry red wine
• 300ml good beef stock
• 1 tsp Dijon mustard
• 1 tbsp cold butter, cubed
• small pinch of salt

Method

1. The night before (or at least 2 hours ahead), pat the tomahawk completely dry with kitchen paper — surface moisture is the enemy of crust, and a dry-brined steak sears properly instead of steaming. Season aggressively all over with the coarse salt and cracked pepper, including the edges and around the bone — be generous, this is a thick steak and most of the salt won't penetrate beyond the surface anyway. Sit it uncovered on a rack set over a tray in the fridge. By cooking time the surface will look dry and slightly tacky — that's the pellicle, and it's what gives you a mahogany crust.
2. Take the steak out of the fridge a full hour before cooking. A cold centre cooks unevenly — you want it sitting at room temperature so the smoke phase is gentle and predictable.
3. Set up the kettle BBQ for two-zone indirect cooking: coals banked to one side only, the other side empty. You're aiming for 110–120°C on the cool side, lid on, vents about a quarter open. Drop a small chunk of oak or beech onto the coals if you have it. Place the steak on the cool side, bone pointing toward the heat — the bone shields the meat closest to it from cooking faster.
4. Slot a probe thermometer into the thickest part of the steak, avoiding the bone. Close the lid and leave it alone. Every peek drops the temperature and adds 5 minutes. After about 60–75 minutes the internal should read 48°C. Pull at exactly 48°C; carryover during the rest takes it to 50–52°C, and the sear adds another couple of degrees — that lands you squarely in medium-rare.
5. Lift the steak onto a board and tent loosely with foil. While it rests for 15 minutes, get the sear zone screaming hot — pile the coals together, open the vents fully, lid off. If you can hold your hand 10cm above the grate for less than 2 seconds, you're there.
6. Brush the steak lightly with the neutral oil (oil on the meat, not the grate — flare-ups char the wrong way). Lay it directly over the coals — and don't crowd the grate, this steak needs full contact with the hottest spot. Sear hard for 90 seconds, lift and rotate 90° for crosshatch, sear another 90 seconds, then flip and repeat on the second side. The crust should be deep mahogany and crackly — if it's still pale, give it another 30 seconds. Sear the fat edge by holding the steak upright with tongs against the bone for 30 seconds.
7. Move the steak back to the cool side. Drop the butter, crushed garlic and herbs into a small cast iron pan and set it over the coals until the butter foams. Watch the garlic — pull the pan off the moment it turns pale gold and fragrant, 30 seconds at most. Burnt garlic turns the whole baste bitter. Spoon the foaming butter over the steak for a full minute, basting constantly — this perfumes the crust without scorching the aromatics.
8. Rest the steak on a warm board for 8–10 minutes. Don't skip this — slice too early and all the juice runs onto the board instead of staying in the meat.
9. While the steak rests, toss the spring onions and lemon halves with the olive oil and a pinch of salt and pepper. Char them directly over the coals — 2 minutes a side for the onions until they blister and go limp, cut-side down for the lemons until deeply caramelised. The lemon juice you'll squeeze later is sweeter and smokier for it.
10. For the sauce, set the cast iron pan with the herb butter back over moderate heat — those stuck garlicky bits in the bottom are the foundation of the sauce. Add the diced shallots and soften for 3 minutes until translucent. Pour in the red wine, scraping the fond off the base, and bubble hard until reduced by two-thirds — syrupy, not watery. Add the stock and reduce again by half. Whisk in the mustard, then pull off the heat and swirl in the cold butter cube by cube until glossy. Taste, season, taste again — adjust the salt now, not at the table.
11. Carve the steak off the bone, then slice across the grain into 1cm strips. The interior should be uniformly pink edge-to-edge with a thin band of crust — that's the reverse-sear payoff. Fan the slices onto a warm board, scatter with flaky salt, pile the charred spring onions alongside, lay a generous handful of watercress at one end, and finish with a squeeze of the smoky lemon over the meat. Pour the red wine sauce over at the table, with the English mustard and horseradish on the side.