Würfelsalat with Horseradish Dressing

How did we arrive at possessing 10 odd tubes of horseradish? The universe must be making a point. Here's our horseradish premiere, please let us know how you like it. It might be something for Christmas.

Cooked beetroots are needed and about the same proportion of cooked potatoes. Cut into cubes.
The carrot, well, was kind of there, but I would not insist on it.
some fresh parsley to top, some green olives.

Now here's the special dressing:

A shallot, finely chopped.
Lemon juice. not too much, just cover the onion.
Salt. We want it.
About half mayonnaise, half yoghurt, leaning towards more yoghurt.
Horseradish, grated fresh (careful) or from one of the many tubes.
Maybe a little olive oil.
Honey.

Yum.