The Ultimate Roast Beef Sandwich

The Ultimate Roast Beef Sandwich – Reverse seared & Sichuan marinated!

Four Ultimate Roast Beef Sandwiches served with ripple chips.

An overnight marinade, combined with low and slow cooking will turn any roast into rave worthy meal. Although suggested cooking time is a helpful guide, a high-quality digital or instant-read thermometer is the best way to monitor for doneness. Every roast is a slightly different weight and thickness and as such will require a different cooking time. I reverse seared this roast on the grill, but it could easily be done in the oven as well.

This roast is delicious served as a traditional dinner with roast potatoes & vegetables, but even better assembled into these mouth-watering sandwiches!

Roast beef dinner platter with carrots, potatoes, brocolini, roasted red pepers and sandwich fixings.

Ingredients

Marinade Ingredients

3.5 lbs Ontario Beef Top Sirloin Roast (Sirloin Tip, Inside or Outside Round work too)
⅔ cup reduced-sodium soy sauce
½ cup rice vinegar
6 green onions, thinly sliced
3-4 cloves local garlic, finely chopped
2 tbsp Sichuan peppercorns, crushed
½ tsp five-spice powder
Salt and freshly ground pepper

Raw ingredients used for a Sichuan marinade for a beef top sirloin roast.

Sandwich Ingredients

Fresh Ciabatta buns or Ciabatta loaf cut into 4-5” portions.
Fire-roasted red pepper (store bought in a jar)
Marinated red onions (recipe link here)
Sautéed sliced cremini mushrooms (sautéed in butter, seasoned with thyme)
Horseradish cream sauce (recipe below)
Baby arugula
Quality blue cheese (optional but recommended)

Preparation

Combine soy sauce, rice vinegar, green onions, garlic, Sichuan peppercorns and five-spice powder in a resealable storage bag or bowl.

Place roast in the bag or bowl, turning to coat. Seal bag or cover bowl and refrigerate for at least 12 hours or for up to 24 hours, turning occasionally if it’s in a bowl.

An image of a beef roast in a sealed bag marinating with a Sichuan marinade.

Preheat the grill to 225°F with a portion of the grill off for indirect cooking.

Remove roast from marinade, reserving marinade. Wipe excess marinade off roast and season all over with salt & pepper.

If use a digital thermometer probe, insert through one end directly in the middle of the roast. Place the roast on the top rack over the portion of the grill that is not on. Place a drip pan on grill under roast. Close lid and cook for 30 minutes.

A (raw) beef roast on the top rack over the portion of the grill that is not on. A drip pan placed under the roast.

Baste with some of the reserved marinade. Close lid and cook for 30 minutes more. Baste again and check temperature (should be approaching 80°F). Close the lid and cook for another 20-30 minutes. Baste again and check temperature.

A finished beef roast on the top rack over the portion of the grill that is not on. A drip pan placed under the roast.

For rare beef (like the one pictured here), remove roast at 100°F (for med-rare, remove roast at 110°F) and transfer to a plate or pan and cover with foil.

An image of grilled roast with a temperature probe reading 101 °F

Heat entire grill on high until temperature reaches about 500°F.
Return beef to hot grill and sear on each side with the lid closed for 2.5-3 minutes per side (assuming 4 ‘sides’). Temperature should be around 108°-110°F (118°-120°F for med-rare).

Remove roast from grill, wrap completely in foil and let rest 10-15 minutes. Finished internal temperature should be 120°-125°F (130°-135°F med-rare)

A rested image of grilled roast with a temperature probe reading 121 °F and ready to carve.

Transfer roast to a cutting board, cut off strings and slice roast thinly across the grain.

Once beef is sliced, toast ciabatta, then layer with a healthy dollop of horseradish cream sauce, a slice of roasted red pepper, a handful of arugula, mushrooms, onions, beef and blue cheese (if using), finish with a little salt and enjoy!

Roast can be made ahead and used later for sandwiches. If making ahead, let whole roast cool, wrap and refrigerate for up to 2 days. Serve sliced at room temperature.

Horseradish Cream Sauce Ingredients

1 cup sour cream
¼ cup fresh hot horseradish
1 tablespoon Dijon mustard
1 teaspoon white balsamic vinegar (champagne or white wine vinegar)
½ teaspoon kosher salt
½ teaspoon freshly ground black pepper

Horseradish Cream Sauce Preparation:

Place all of the ingredients into a mixing bowl and whisk until the mixture is smooth. Place in the refrigerator for at least 4 hours or overnight to allow flavors to combine.

Make ahead and store in an airtight container for up to a week.