1 cup of grated horseradish (grated by hand on the medium side of the box grater or in a food processor)
1/4 cup distilled white vinegar
1 tsp salt
1 tsp sugar
Combine all ingredients.
If you grate fresh horseradish in a food processor, be careful when you open the processor bowl. The fumes of horseradish-like its cousin, mustard-can burn your eyes or sinus passages.