Wash the cucumber and slice into thin slices. Peel and finely chop the onion. Wash the dill, dab dry and chop finely. Mix vinegar, onion and mustard. Season with salt, pepper and sugar. Whip the oil into it.
Add cucumber slicer to the vinaigrette and mix. Spread bread with fat. Heat clarified butter in a frying pan, add eggs and allow to set at medium heat. Season with salt and pepper. Cover bread with ham and fried egg. Arrange bread and cucumber salad on a plate and serve garnished with tomato and parsley as desired