Steak Frites Recipe

Make compound butter

In a small bowl, combine softened unsalted butter, chopped parsley, minced garlic, lemon zest, chopped thyme, fine sea salt, and freshly ground black pepper. Mix thoroughly until homogenous. Transfer mixture to a piece of plastic wrap or parchment, shape into a log (about 1" diameter), wrap tightly and chill in the refrigerator for at least 30 minutes (can refrigerate up to 3 days) to firm up.

Prep potatoes

Cut the scrubbed russet potatoes into 1/4"–3/8" sticks (uniform thickness for even cooking). Rinse the cut fries under cold water until the water runs clear to remove surface starch, then transfer to a bowl of cold water and chill for 20–30 minutes. Drain and pat completely dry with clean kitchen towels or paper towels.

Fry in two stages (preferred)

Heat oil in a deep heavy pot or deep fryer to 325°F (163°C). Working in batches, fry the dried potato sticks for 3–4 minutes until softened and pale — do not let them brown. Remove with a slotted spoon and drain on paper towels. Increase oil temperature to 375°F (190°C). Fry the par-cooked fries again, in batches, for 2–3 minutes until golden-brown and crisp. Drain on paper towels.

Season fries

While still hot, immediately toss fries in a large bowl with fine sea salt, black pepper, and truffle oil. Add grated Parmesan if using and toss to combine. Sprinkle chopped parsley for color. Keep warm in a single layer on a tray in a low oven (200°F / 93°C) if needed while finishing steak.

Bring steak to room temperature & season

Pat the top sirloin dry with paper towels and let it rest at room temperature for 20–30 minutes. Rub both sides lightly with olive oil, then season liberally with kosher salt and freshly ground black pepper, pressing the seasoning into the meat.

Grill or pan-sear steak

Preheat a grill to high (or a heavy skillet cast-iron pan over high heat) until very hot. If using a grill, oil the grates. Sear the steak 3–4 minutes per side for medium-rare (internal temperature about 125–130°F/52–54°C), adjusting time for thickness and desired doneness. For crosshatch grill marks, rotate 90° halfway through each side's cooking. For pan method, sear edges for 30–45 seconds to render fat if present.

Rest and finish

Transfer the steak to a cutting board and tent loosely with foil. Rest for 8–10 minutes to allow juices to redistribute. While still warm, slice the steak thinly against the grain into 1/4" slices. Top the sliced steak with 1/2" rounds of chilled compound butter (slice from the log made earlier) so it melts over the meat. Sprinkle a pinch of coarse finishing salt on the meat if desired.

Divide the truffle fries among plates. Fan sliced steak alongside or atop fries as desired. Place compound butter melts on the hot steak so they melt and glaze the meat. Garnish fries with additional Parmesan or parsley, and serve with lemon wedges on the side for optional brightness. Serve immediately.