5 large dry sea scallops (about 4 to 5 ounces)
Kosher salt and freshly ground black pepper
1 tablespoon unsalted butter
1 tablespoon finely minced shallot
1 pinch celery seed
3 tablespoons dry sherry, such as amontillado
1 teaspoon sherry vinegar (white or red wine vinegar is fine, too)
1 tablespoon prepared horseradish
2 tablespoons heavy cream
Chopped chives, for garnish (optional)
Lemon wedges, for serving (optional)
Pat scallops dry with a paper towel or clean kitchen towel and season with salt and pepper.
Heat a small skillet over medium-high heat and melt the butter in it. Add the scallops and cook about 2 to 3 minutes on the first side without touching, then flip and cook another 1 to 2 minutes on the second side, just until they’re opaque. Remove scallops from the pan and set aside somewhere warm.
Taking the pan off the heat, add the shallot and celery seed and sauté about 1 minute. Place pan back over medium heat this time; add the sherry, vinegar, and horseradish; and let bubble up and reduce by half, about 1 to 2 minutes. Add the cream and bring to a gentle simmer to warm through and reduce sauce slightly to your desired thickness, another minute or so.
Transfer the sauce to a plate, then top with the scallops. Garnish with chopped chives and serve with lemon wedges.