Ingredients You'll Need

To make the ultimate deli-style sandwich, high-quality ingredients make all the difference. Here is what you will need to grab on your next grocery run:

For the Sandwiches:

• 12–16 slices roast beef: Look for thinly sliced, premium deli roast beef (like top round or rare roast beef) for the best texture.

• 4 sandwich rolls: Sub rolls, hoagie buns, or fresh baguette pieces work beautifully.

• 2 tablespoons butter: For perfectly toasting your bread.

• 1 cup arugula or lettuce: Arugula adds a wonderful peppery crunch that pairs perfectly with beef.

• 1 large tomato: Sliced thin.

• 1 small red onion: Thinly sliced for a sharp, crisp bite.

• Pickles (optional): For a touch of acidity and crunch.

For the Creamy Horseradish Sauce:

• ½ cup mayonnaise: The rich base for your spread.

• 2–3 tablespoons prepared horseradish: Adjust this based on how much "clear-your-sinuses" kick you prefer.

• 1 teaspoon Dijon mustard: Adds a tangy depth of flavor.

• 1 teaspoon lemon juice: Cuts through the richness of the mayo and beef.

• Salt and black pepper: To taste.

Step-by-Step Instructions

1. Mix the Horseradish Sauce

In a small mixing bowl, combine the mayonnaise, prepared horseradish, Dijon mustard, lemon juice, salt, and black pepper. Whisk until the sauce is completely smooth and creamy. Taste and adjust the horseradish if you want more heat.

2. Prepare and Toast the Bread

Slice your sandwich rolls in half horizontally. Melt the butter in a pan over medium heat and place the rolls face down. Toast until they are golden brown and slightly crispy. Pro-tip: Toasting creates a barrier that keeps your bread from getting soggy!

3. Spread the Sauce

Spread a generous, even layer of your homemade horseradish mayo on both the top and bottom pieces of the toasted bread.

4. Layer and Assemble

On the bottom bun, layer the thinly sliced roast beef. To create volume, ribbon or fold the meat rather than laying it flat. Top the beef with your fresh arugula or lettuce, tomato slices, red onion, and pickles (if using).

5. Serve and Enjoy

Place the top bun over the layers, press down gently so the flavors mingle, and slice the sandwich diagonally in half. Serve immediately while the bread is still fresh and crispy!

Pro-Tips for the Best Roast Beef Sandwich

💡 Warm It Up: If you prefer a warm sandwich, wrap the roast beef slices in foil and heat them in a toaster oven for 2–3 minutes before assembling.

💡 Add Cheese: Melt a slice of Swiss, provolone, or sharp white cheddar onto the bread during the last 30 seconds of toasting.

💡 Customize the Heat: Prepared horseradish loses its potency over time. For the best flavor explosion, make sure your jar of horseradish is relatively fresh.

Frequently Asked Questions (FAQs)

What goes best with a roast beef sandwich?

This sandwich pairs perfectly with classic deli sides like potato chips, a crisp green salad, French fries, or a cup of warm potato leek soup.

Can I make the horseradish sauce ahead of time?

Yes! In fact, making the horseradish sauce 24 hours in advance and letting it sit in the fridge allows the flavors to meld together, making it even more delicious. Store it in an airtight container for up to a week.

What is the best bread for a roast beef sandwich?

Sturdier breads hold up best to the heavy layers of meat and sauce. Baguettes, ciabatta rolls, hoagie rolls, or thick slices of sourdough are excellent choices.