1 5" long daikon, scrubbed and peeled (roughly equal in weight to the carrots)
1/2 cucumber, peeled
1 tsp prepared horseradish (more or less according to your taste and desired heat)
1/3 cup mayo
1/2 cup sour cream
Grate carrot, cucumber and daikon together into a medium bowl. Stir in horseradish and a pinch of salt. Add a spoonful of mayo and two heaping spoonfuls of sour cream. Mix well, adding additional mayo or sour cream1 as needed to pull the salad together. Taste, adjust horseradish2 and salt as needed.
As for the sour cream and mayo, as always, I used more sour cream than mayo. I added just enough to bind the veggies into a cohesive, creamy salad.
This is another one of those recipes that really depends on the cook's judgment. My horseradish, prepared at home, is somewhat spicier than store-bought and different people react to horseradish in different ways. You want enough to be felt but not enough to overpower.