Cook potatoes, peel and cut into discs. The broth is heated and to it add the vinegar, the oil, sugar, mustard, salt and pepper. Stir a few minutes until homogeneous. Cucumbers, apples, bacon and onion cut into cubes. Bacon lightly fry, almost no fat. Mix with potatoes and pour broth. Add and gherkins and apples. All well stir until liquid is absorbed. Serve decorated with basil leaves.