Cut the potatoes into bite-sized pieces. Put them in a pan of lightly salted water, then bring to the boil and cook for 10-15 minutes until tender.
Meanwhile, cut the beetroot into small bits. Cut the anchovy into 3 equal pieces. Finely chop the onion and dill. Put all of these into a large bowl.
When the potatoes are cooked, drain then add them to the beetroot and anchovies.
Add the vinegar and some of the anchovy's oil and some olive oil to your taste.
Toss gently, season to taste and serve warm or at room temperature.