Peel the cucumber and slice it. Season with salt and pepper and let steep for 15 minutes. In the meantime, fry the ham cubes with a splash of oil (there must not be too much oil, but the ham cubes will not be crispy without oil). Drain half of the cucumber water. Stir in the chopped chives and the sour cream. Just before serving, fold in the diced ham and season with salt and pepper.
You can also use sour cream instead of sour cream, but then add 1-2 tablespoons of table vinegar to taste.