Roast Beef Bistro Dip Recipe

Season

Remove beef from refrigerator 45 minutes before roasting to come closer to room temperature. Pat dry with paper towels. Mix kosher salt, black pepper, garlic powder, and dried thyme; rub evenly over entire roast.

Sear

Preheat oven to 230°C (450°F). Heat vegetable oil in a large ovenproof skillet or roasting pan over high heat until shimmering. Sear roast 2–3 minutes per side until well browned on all sides to develop flavor.

Roast

Transfer pan to oven and roast at 230°C (450°F) for 15 minutes to set crust, then reduce oven to 160°C (325°F) and continue roasting until internal temperature reaches 54°C (130°F) for medium-rare (about 20–30 more minutes depending on roast thickness). Use an instant-read thermometer to check.

Rest & Slice

Remove roast from oven, tent loosely with foil and rest 15–20 minutes (temperature will rise a few degrees). Using a sharp slicing knife, slice roast beef very thinly against the grain into 2–3 mm slices. Reserve any pan juices for the au jus base.

Prepare Base

In a medium saucepan over medium heat, melt butter. Add minced shallot and crushed garlic; sauté 1–2 minutes until translucent and aromatic but not browned.

Deglaze

Add red wine (if using) to the pan to deglaze, scraping up any browned bits from the roast pan or skillet. Simmer 1–2 minutes to reduce slightly.

Combine Stocks

Pour beef demi-glace and beef stock into the saucepan. Add soy sauce and Worcestershire sauce. If you reserved pan juices from roasting, add them now. Bring to a gentle simmer, reduce heat to low and let simmer 8–10 minutes to concentrate flavors.

Finish

Taste and season with salt and freshly ground black pepper. Strain the au jus through a fine mesh sieve into a clean container to remove solids for a refined clear au jus. Keep warm; reserve about 150 ml for dipping service.

Prepare Baguette

Preheat oven to 190°C (375°F). Slice each baguette portion lengthwise but not completely through to form a hinge. Spread softened butter evenly on cut sides and, if using, spread grainy mustard on one side.

Warm & Toast

Place buttered baguettes on a baking sheet and warm in the oven 6–8 minutes until butter melts and edges are lightly crisp. If you prefer melted cheese, open baguette and place cheese slices inside, then return to oven 2–3 minutes more until cheese is melted.

Fill

Pile thin slices of the rested roast beef onto the warm baguette (about 150–200 g sliced beef per sandwich). Close the sandwich slightly to meld flavors.

Serve

Transfer sandwich to a plate, place a small dipping bowl with reserved hot au jus alongside, and serve immediately with fries.

Prep Potatoes

If using fresh potatoes, cut peeled potatoes into 9–10 mm (about 3/8 inch) sticks. Rinse in cold water until water runs clear to remove starch, then drain and pat dry thoroughly with clean towels. For crisper fries, soak in cold water for 30 minutes, then drain and dry.

First Fry (Blanch)

Heat vegetable oil in a deep fryer or heavy pot to 160°C (320°F). Fry potatoes in batches 4–5 minutes until pale and tender but not browned. Remove and drain on wire rack or paper towels.

Second Fry (Crisp)

Increase oil temperature to 190°C (375°F). Fry blanched fries in batches 2–3 minutes until golden and crispy. Drain on paper towels, immediately season with salt and pepper, and toss with chopped parsley if desired.

Plate the sandwich with fries, garnish fries with parsley, place thyme sprigs beside sandwich for aroma, and provide the warm strained au jus in a dipping vessel. Recommend diners dip beef slices or the sandwich into the au jus for classic bistro flavor.