Wash the plaice, dab dry, sprinkle with lemon juice and leave to stand for a while. Peel and wash the potatoes, cover and cook in salted water for about 20 minutes.
Mix vinegar, salt, pepper and 1 pinch of sugar. Fold in the oil. Clean, wash and pluck the salads. Wash and slice the tomatoes. Peel onions. Cut 1 onion into rings.
Wash parsley and chop finely.
Dice 2 onions. Cut the bacon into strips and fry them crisply in two pans without fat. Fry the onion cubes briefly. Remove bacon and onions from the pans together with the bacon fat and keep warm.
Pat the plaice dry. Season with salt and pepper. Spread the flour on a flat plate. Turn the plaice in it and tap off the excess flour. Heat 1 tablespoon of clarified butter in each of the two pans.
First fry 1 plaice in it on the light side for 3-4 minutes until golden brown. Then turn and fry on the dark side for 3-4 minutes. Remove the plaice and keep warm. Fry the remaining plaice in the same way and take them out.
Drain the potatoes. Mix salad, onion rings, tomatoes and vinaigrette. Arrange the plaice with potatoes and bacon and sprinkle with parsley. Add salad.