Though fresh horseradish is in season around Easter, you can substitute drained bottled horseradish. We recommend using the cooked beets left over from the pickled quail egg recipe , but if you're not making the eggs, you can substitute canned beets.

Ingredients

　　1 cup finely grated peeled fresh horseradish (1/2 lb; use small teardrop-shaped holes of a box grater)

　　3 cooked medium beets (reserved from pickled quail eggs , peeled and coarsely chopped (1 3/4 cups)

　　1/2 teaspoon salt

　　1/2 teaspoon sugar

　　1/4 cup cider vinegar

　　Coarsely purée all ingredients in a food processor, scraping down side of bowl as needed, 30 to 40 seconds. Let stand, covered, at room temperature at least 1 hour (for flavors to develop).