Make a deep horizontal incision lengthwise in the pork tenderloin. Widen the opening. Chop parsley, basil, sage, pecorino and parmesan finely and mix with breadcrumbs, salt and pepper. Now fill the pork and then wrap it loosely in pancetta.
Fix the whole thing with kitchen string or roulade needles.
Heat 2 tablespoons of oil in a frying pan. Sauté the scarlet, garlic, sage, thyme, rosemary and meat vigorously, add diced potatoes and fry with them. Pour 1 glass of white wine and 1/2 glass of stock and fry in a preheated tube on the lower rack for about 40 minutes at 180°C.
Then let the meat rest for 5 minutes at residual heat.