Grease a roasting tin with the vegetable oil, add the pork and roast for about 25 minutes or until cooked through. Turn the pork once or twice during cooking. (You can also use leftover roast pork or even beef). Slice the pork.
Boil the beetroot for 20 minutes or until tender, then drain, cool, peel and chop into cubes.
Cook the potatoes in boiling water until tender, drain, cool, peel and quarter.
Place the pork, beetroot and potatoes in a large bowl with the dill pickles, onion, radish and chopped eggs.
Combine the olive oil and vinegar, season with salt and pepper to taste, pour over the salad and mix gently. Stir in the mayonnaise, then garnish with tomatoes.