- 1/2 cup good-quality sour cream
- 1 tablespoon prepared horseradish
- 2 tablespoons unsweetened all-natural applesauce
- 2 tablespoons panko or plain breadcrumbs
- 2 tablespoons finely chopped chives
- Salt and coarse black pepper
- 8 slices white or peasant bread from a large round loaf
- 8 slices rare roast beef or about 2/3 to 3/4 pound thinly sliced leftover steaks of any cut
- 1/4 cup minced red onion or 1 large shallot, finely chopped
- A handful flat-leaf parsley, very finely chopped
- 1 small red chile pepper, such as fresno or cherry, seeded and finely chopped
- Zest of 1 lemon
- 1 small bunch watercress--trimmed, cleaned and dried
- 1/2 pound brick of the sharpest white cheddar available to you, thinly sliced (itll be crumbly if its very sharp)
Combine the sauce ingredients. Heat a panini press, cast-iron skillet or griddle over medium to medium-high heat.
On a work surface, spread the horseradish sauce liberally over 4 slices of bread. Arrange 2 slices of rare roast beef over the sauce. Combine the red onion (or shallot) with the parsley, chile pepper and lemon zest and sprinkle liberally over the roast beef. Arrange a layer of watercress over the beef. Divide the cheese evenly among the sandwiches and set the remaining bread slices in place. Press the panini 2 at a time on the panini press or in a hot skillet with a pan weighted on top.