Grate the beetroot. Roast the optional nuts and add them (but do not cut them very small beforehand). Also add the prunes whole (or cut in half if they are too big). Peel and squeeze the garlic and stir in with the mayonnaise. Season to taste with sugar, salt and pepper.
The salad tastes best if you let the salad stand in the refrigerator for a few hours and then serve it cold.
Tip: You can also omit the garlic. Add more sugar and it will taste wonderfully mild.