Bring the potatoes to the boil in salted water and then turn down to a simmer. When cooked, drain and allow to steam for a couple of minutes before ripping into pieces.
Finely slice the spring onions. Juice the lemon.
Toast the nuts quickly in a preheated pan, remove.
Fry the bacon lardons until crispy in the same pan and then add the ripped boiled potatoes . Leave to caramelize or color before stirring again.
Whisk together the sherry vinegar and the mustard. Slowly pour in the olive oil and walnut oil to emulsify the dressing. Season with black pepper.
Pick and wash the watercress. Dry in a salad spinner. Dress with the sherry vinegar and mustard dressing.
Add the sauteed potato and bacon to the salad ingredients, nuts and the dressing as needed.
«This potato salad can easily be turned into potato cakes. Omit the lemon juice and then make the mixture into patties. Pan fry until golden brown and serve alongside any meat or white fish.»