Sandwiches · American
Roast Beef Sandwich
Ruffled roast beef, zippy horseradish cream and quick-pickled onions on a toasted roll.
- Hands-on
- 30 min
- Hands-off
- 50 min
- Oven preheat
- 5 min
- Total
- 1 h 20 min
- Makes
- 6 sandwiches
- Serves
- 6
Most of the time is waiting: the salted onion rests 20 minutes, then pickles at least 30 minutes while the sauce chills (also at least 30). Toasting takes about a minute. Recipes list 1 hr 30 min in total; our figure counts the minimum waits.
- easy
- lunch
- no-cook-filling
- picnic
Verified against at least two trusted test kitchens or food-safety guides · Last checked · What this means
Scaling? Scales in a straight line. You'll have pickled onions and sauce to spare if you make fewer sandwiches; see storage. Some items (like eggs) don’t halve neatly: beat them, then measure out half.
Ingredients
You need: 2 small bowls · sieve or colander · baking sheet · oven broiler (grill); the source gives no setting · bread knife · spoon for scooping the rolls · oven mitts
Contains: egg · milk · wheat
Method
Salt the onion
Toss the sliced red onion with 1 tbsp kosher salt and leave it for 20 minutes.
Pickle the onion
Rinse the onion under cold water, drain it and squeeze out the extra liquid. Mix it with 90 ml (6 tbsp) red wine vinegar and leave it for at least 30 minutes (up to 24 hours in the fridge).
Otto tried this firstOtto skips the rinse. The onions taste like a salt lick. Rinse after the 20-minute salt rest.Make the horseradish sauce
Stir together 175 ml (3/4 cup) mayonnaise, 175 ml (3/4 cup) sour cream, 90 ml (1/4 cup + 2 tbsp) horseradish with its liquid, 1/2 tsp lemon zest and 2 tsp kosher salt. Add black pepper and hot sauce to taste. Refrigerate for at least 30 minutes.
Toast the rolls
Heat the broiler (grill). Halve the 6 rolls, scoop out a little of the soft middle from each half so the filling sits snugly, and set them cut-side up on a baking sheet. Broil for about 1 minute. Stay at the oven: it goes from golden to burnt fast.
Ready when: The cut sides are lightly golden and crisp at the edges. Pull them sooner if they start to darken.
Otto tried this firstOtto goes to fetch the tomatoes and comes back to charcoal. Broilers need watching for every second of that minute.Build the sandwiches
Spread horseradish sauce inside each roll. On each bottom half lay 2 tomato slices and season with salt and pepper. Drape about 113 g (4 oz) roast beef over the tomato in loose folds, season again, then top with pickled onion and a handful of the 3 cups greens. Close and serve right away.
Swaps
- Instead of watercress: arugula (rocket), same amount They're interchangeable here.
- Instead of Kaiser rolls and mayo-sour cream sauce: buttered brioche buns with a horseradish crème fraîche A British-style take on the same sandwich, with watercress and freshly grated horseradish.
Make ahead, store & reheat
- Make ahead
- The onions can pickle for up to 24 hours; keep them in the fridge. Make the sauce at least 30 minutes ahead so it can chill. Toast and assemble just before eating.
- Storage
- Assembled sandwiches are best eaten straight away. An opened pack of deli roast beef keeps 3 to 5 days in the fridge.
Good to know
- Scooping a little bread out of each roll stops the filling sliding out.
- Drape the beef in loose folds rather than flat slices: it stacks taller and is easier to bite.
Safety
- Deli meats can carry Listeria. If you're pregnant, 65 or older, or have a weakened immune system, eat deli meat only when it has been heated to 74°C (165°F) or until steaming hot.
- The broiler is very hot and close to the food. Use oven mitts, keep the oven door watched, and kids should let an adult handle the tray.
- Keep the sauce and the beef in the fridge until you assemble; don't leave them out for more than 2 hours.
- Check the labels on the rolls, mayonnaise and horseradish for allergens.