Remove the peel from the beet and cut into fine slices. Halve the onion and cut vertically into very fine slices. Remove the skin from the horseradish and grate it on the fine side of the grater. Mix everything well.
Stir mustard, dill, vinegar and caraway seeds to make a sauce. Season well with salt and freshly ground pepper. Pour the sauce over the beets, mix well and let sit at kitchen temperature for one to 120 minutes with the lid closed.
Tip: You can keep this leaf salad in the refrigerator for 1 to 2 days. It will only get better. However, you should mix in the onion just before serving.
Variation Omit the horseradish and add a tiny bit of grated orange zest and juice.
Our tip: Use high-quality red wine for an especially fine taste!