Wash the potatoes and cook in boiling water for about 20 minutes. Stir yoghurt and mayonnaise with 2 tablespoons of cucumber water until smooth. Wash the fish and pat dry. Cut the cucumbers into slices.
Wash the apple, quarter it, cut out the core. Cut apple into slices. Mix apple, cucumber and sauce. Season to taste with salt and pepper. For the vinaigrette, whisk vinegar, salt, pepper and honey.
Add oil drop by drop. Peel the shallot, cut into fine cubes and stir into the vinaigrette. Clean the salad, remove the leaves from the stalk, wash and shake dry. Peel carrot and cut into thin slices.
Clean, wash and slice the spring onions. Peel red onion and cut into rings. Peel remaining onion and cut into cubes. Potatoes quench, peel and cut into slices.
Heat the lard in a pan and fry the potatoes for about 7 minutes, turning them carefully. Fry bacon and diced onion for the last 3 minutes. Mix salad ingredients with vinaigrette. Arrange salad, potatoes and matie with sauce on plates.
Place onion rings over the matie.