Hot Pastrami Sandwich Recipe

In a small bowl, combine 3 tbsp Dijon mustard, 1 tbsp prepared horseradish, 3 tbsp mayonnaise, 1 tsp fresh lemon juice and 1 tsp honey.

Whisk until smooth and homogenous. Season with 1/4 tsp kosher salt and 1/4 tsp freshly ground black pepper; taste and adjust honey, lemon or horseradish to balance heat and acidity.

Cover and refrigerate while you assemble the sandwich. Dressing can be made up to 3 days ahead.

Prepare the baguette

Preheat a skillet or griddle over medium heat (or preheat oven to 375°F / 190°C if using oven). Cut the baguette lengthwise, leaving a hinge if desired, to make two long halves. Lightly butter the cut faces with 2 tbsp softened butter (spread evenly).

Dress the bread

Spread about 2–3 tbsp of the Dijon-horseradish dressing on the bottom half of the baguette and reserve 1–2 tbsp for serving. On the top half, spread a thin layer of any remaining butter to help toasting and flavor.

Assemble with pastrami and cheese

Pile the thinly sliced hot pastrami evenly onto the bottom half of the baguette (about 12 oz total). Distribute 6 oz sliced Emmentaler cheese over the pastrami in an even layer. Season lightly with 1 tsp freshly cracked black pepper. If using, add sliced gherkins or dill pickles in a single layer over the cheese or on the side.

Heat and melt

Option A — Stovetop/griddle: Place the sandwich on the preheated skillet, press gently with a heavy pan or a sandwich press, and cover with a lid. Toast for 3–5 minutes until the buttered bread is golden and cheese is melted, flipping once if necessary. Option B — Oven: Place the assembled sandwich on a baking sheet and bake at 375°F (190°C) for 8–10 minutes, then switch to broil for 1–2 minutes if you want a crisper top—watch closely to avoid burning.

Finish and serve

Transfer the sandwich to a cutting board. Let rest 1 minute, then slice into 4 equal portions. Serve immediately with any reserved Dijon-horseradish dressing on the side for dipping and pickle slices alongside.