Prime Rib French Dip Recipe

Prep roast

Remove the prime rib from the refrigerator 1 hour before cooking to come closer to room temperature. Pat dry with paper towels.

Make herb garlic paste

In a small bowl combine minced garlic, chopped rosemary, chopped thyme, softened butter and olive oil. Season with kosher salt and freshly ground black pepper and stir to make a paste.

Rub the paste all over the roast, pressing into the surface. Place roast on a rack in a roasting pan with the fat cap up.

Preheat oven to 500°F (260°C). Roast at 500°F for 15 minutes to develop a crust, then reduce oven temperature to 325°F (160°C) and continue roasting until internal temperature reaches 120°F (49°C) for rare or 125°F (52°C) for medium-rare (about 12-15 minutes per pound after initial sear, use instant-read thermometer).

Remove roast from oven, tent loosely with foil and rest for 20-30 minutes. Reserve pan drippings for the jus.

When rested, thinly slice roast against the grain to yield enough slices for 6 sandwiches (about 1/4 inch thick). Keep warm.

While the roast cooks or rests, melt 1 tbs butter with 1 tbs olive oil in a skillet over medium heat. Add the thinly sliced onions and cook, stirring occasionally, until translucent, about 8 minutes.

Increase heat to medium-high, add the red wine and use a wooden spoon to scrape any browned bits from the pan. Add the beef stock, brown sugar, thyme, salt and pepper.

Simmer gently until liquid reduces to a glossy, syrupy consistency and onions are very soft, about 15-20 minutes. Taste and adjust seasoning. Keep warm.

In a small bowl combine the Boursin-style cheese, prepared horseradish, lemon juice, chopped chives, salt and pepper. Stir until smooth and taste — add more horseradish if you prefer more heat. Refrigerate until assembly.

After removing the roast, pour off excess fat from the roasting pan leaving about 2 tablespoons of drippings. Place the pan over medium heat (or use a saucepan with 2 tbs beef fat). Add the minced shallot and cook until softened, about 1-2 minutes.

Sprinkle the flour over the shallot and stir to form a roux, cooking 30-45 seconds. Deglaze with 1/2 cup red wine, scraping brown bits from the pan. Let the wine reduce by half.

Add 2 cups beef stock, thyme sprig and bay leaf. Bring to a simmer and reduce for 8-12 minutes until slightly thickened. Remove thyme sprig and bay leaf, season with salt and pepper. Strain through a fine-mesh sieve into a bowl or small saucepan and keep warm. Adjust seasoning.

Preheat broiler or a skillet. Split the rolls and spread a thin layer of the horseradish Boursin on the bottom halves.

Pile warm sliced prime rib on top of the Boursin, add a generous spoonful of red wine braised onions, then top with a slice or two of Havarti. Close sandwiches with tops of rolls.

Butter the outside of each roll lightly and place sandwiches under the broiler or in a hot skillet for 1-2 minutes until the Havarti melts and the rolls are golden—watch carefully to avoid burning.

Serve each sandwich with a small bowl of warm jus for dipping. Optionally sprinkle coarse salt on top and add extra horseradish Boursin on the side.