Onglet Steak & Chips Recipe

Prepare potatoes

Peel if desired and cut russet potatoes into 1/2-inch matchstick fries. Rinse cut potatoes under cold water until water runs clear to remove excess starch. Place in a bowl of cold water and refrigerate for at least 30 minutes (or up to 2 hours) to crisp.

Dry and par-cook

Drain the potatoes and dry thoroughly with a clean kitchen towel or paper towels. Heat vegetable oil in a deep pot or heavy pan to 325°F (160°C). Fry potatoes in batches for 4–5 minutes until soft but not browned. Remove to a single layer on a rack or paper towels to drain. Let cool 10 minutes.

Finish frying

Increase oil temperature to 375°F (190°C). Fry par-cooked potatoes in batches for 2–3 minutes until golden-brown and crisp. Remove, drain on paper towels, season immediately with fine sea salt and freshly ground black pepper, and keep warm.

Bring steak to room temperature & season

Remove the onglet steak from the refrigerator 30–45 minutes before cooking to come to room temperature. Pat dry with paper towels. Evenly season both sides with kosher salt and freshly ground black pepper.

Sear the steak

Heat a heavy skillet (cast iron preferred) over high heat until smoking. Add neutral oil and swirl to coat. Place steak in the pan and sear, without moving, for 2.5–3 minutes until a dark crust forms. Flip and add 1 tablespoon butter, crushed garlic clove and thyme sprigs to the pan. Tilt the pan and spoon melted butter over the steak (baste) for another 2–3 minutes for medium-rare (internal temperature ~130–135°F / 54–57°C). Adjust time for desired doneness.

Rest steak

Transfer steak to a cutting board, tent loosely with foil, and rest for 8–10 minutes. Resting allows juices to redistribute; it also finishes carryover cooking.

Slice

Trim any membrane if present and slice onglet steak against the grain into 1/4-inch slices. Keep slices warm while finishing sauce and plating.

Sauté shallot and deglaze

After removing the steak from the pan (keep pan with fond), reduce heat to medium. Add the minced shallot to the pan and sauté in any remaining fat for 1 minute until softened (add a little butter if pan is dry). Carefully add the brandy or cognac and flambé or simmer for 30–45 seconds to burn off alcohol, scraping up browned bits from the pan.

Build the sauce

Add the crushed green peppercorns and the beef stock to the pan. Simmer gently until the liquid reduces by about half, about 3–4 minutes. Stir in the double cream and Dijon mustard and continue to simmer until the sauce thickens slightly, 2–3 minutes.

Finish and season

Remove the pan from the heat and whisk in the cold cubed butter piece by piece to give the sauce a glossy finish. Taste and season with salt as needed. If sauce is too thick, loosen with a tablespoon of stock or water.

Arrange a portion of chips on each plate. Fan sliced onglet steak over or beside the chips. Spoon peppercorn sauce over the steak or serve in a small jug alongside. Sprinkle chopped parsley over the chips and steak. Serve immediately with lemon wedges on the side if using.