Looking for the ultimate steak sandwich? This version layers pan-seared ribeye, sautéed mushrooms, caramelized onions, and a zesty horseradish mayo on crusty ciabatta — a sandwich to savor.
When asked recently to name my top five sandwiches, I assumed it would be easy — until it wasn’t. I love sandwiches in every form: simple grilled cheese, a brunch-ready Croque Madame, or a hearty New Jersey-style Sloppy Joe. Narrowing favorites felt like choosing a single favorite cheese or wine — impossible when so many are worth keeping.
Steak sandwiches, though, consistently rise near the top of my list. Tender, medium-rare slices of beef tucked into crusty artisan bread that soaks up every savory drop: add a few bright greens and a flavored mayo or aioli, and you have something special. This particular steak sandwich with horseradish mayo earned a firm second on my list — comforting, bold, and remarkably simple to assemble.
Making Horseradish Mayo
Flavored mayonnaise is an effortless way to elevate any sandwich. A few added ingredients — in this case prepared horseradish, garlic, and freshly ground black pepper — transform plain mayo into a tangy, bistro-style spread that pairs perfectly with rich beef.
For this recipe I stir together mayonnaise, a spoonful of sour cream, minced garlic, and refrigerated prepared horseradish, seasoning with salt and pepper. Let the mixture rest in the refrigerator for at least 30 minutes so the horseradish can fully develop; it often tastes muted right after mixing but brightens as it chills. Adjust the horseradish amount to match your preferred heat level and the intensity of the brand you use.
What is Prepared Horseradish?
Prepared horseradish in the U.S. is grated horseradish root preserved with vinegar and salt, usually jarred and sometimes labeled “pure” horseradish. It differs from cream-style horseradish or horseradish sauce, which mix the root into a creamy base. For the best flavor, choose refrigerated jars from the produce, deli, or seafood sections rather than shelf-stable varieties that often contain fillers. The ingredient list should be straightforward: horseradish root, vinegar, salt, and occasionally natural flavor. Look for a creamy color in the jar; a brown tint usually indicates the jar is older and less potent.
Customizing the Heat
Brands vary widely in spiciness. Start with the smaller amount called for and taste after the mayo chills. If you want more kick, add additional prepared horseradish a little at a time until it reaches your preferred heat. Remember that the flavor intensifies as the mayo rests.
Assembling the Ultimate Steak Sandwich
This sandwich is best made with butter-basted, pan-seared steak — a well-marbled ribeye is ideal, though any favorite steak cut works. Grilled steak is a fine substitute in warm-weather months. Ciabatta rolls are my bread of choice: their crisp crust and airy crumb handle juicy sliced steak and toppings exceptionally well.
Classic add-ins like caramelized onions and sautéed mushrooms pair beautifully with beef. You can prepare the onions and mushrooms a day ahead for faster assembly; gently rewarm them before serving. The richness of the steak and toppings benefits from a bright, peppery bite: baby arugula adds that freshness and balances the sandwich. Swap in spring mix or romaine if you prefer.
These sandwiches are satisfying without cheese, but if you want a melty element, Swiss or provolone melt nicely over the warm steak.
Serving Steak Sandwiches
Serve the sandwiches while the steak is still warm for the best texture and juiciness. They hold up at room temperature but are most satisfying hot. I like to serve them with crisp shoestring fries and extra horseradish mayo for dipping — the mayo doubles as an excellent fry sauce. A cold, crisp beer or your favorite beverage completes the casual, flavorful meal.
Steak Sandwich Recipe with Horseradish Mayo
Amanda Biddle
Ingredients
- 4 ciabatta rolls (about 6 inches long), split lengthwise
- 2 pan-seared steaks, sliced (about 12 ounces each, 1–1½ inches thick)
- 8 ounces sliced cremini mushrooms
- 1 tablespoon unsalted butter
- ½ cup caramelized onions
- ½ cup baby arugula
- Kosher salt and freshly ground black pepper
Horseradish Mayo
- ½ cup mayonnaise
- 1 tablespoon sour cream
- 1 large garlic clove, minced
- 1–2 tablespoons refrigerated prepared horseradish, drained
- Kosher salt and freshly ground black pepper, to taste
Instructions
Prep the Sandwiches
- Cook the steaks to your desired doneness following your preferred pan-seared steak method; let rest, then slice.
- Make caramelized onions and sautéed mushrooms. For mushrooms: heat butter in a skillet over medium-high, add mushrooms with a pinch of salt and pepper, sauté until liquid evaporates and edges brown, then set aside.
Make the Horseradish Mayo
- Whisk together mayonnaise, sour cream, minced garlic, horseradish, and a pinch of salt and pepper. Cover and refrigerate at least 30 minutes to let flavors meld.
- Taste after chilling and add more horseradish if desired. Keep chilled until assembly.
Assemble the Sandwiches
- Spread a little horseradish mayo on the bottom of each ciabatta roll. Layer baby arugula, a quarter of the sliced steak, sautéed mushrooms, and caramelized onions. Add more mayo to the top half if desired.
- Serve immediately while the steak is warm for the best texture and flavor.
Nutrition Estimate
Nutrition information is automatically calculated and should be used as an approximation.
These recipes use US customary measurements and have not been tested for high altitude cooking or baking.