Cut the ciabatta buns into 8 slices. Heat oil in a pot. Fry the rolls for about 2 minutes on each side until golden brown. Take out and drain on kitchen paper. Wash the slices, dab dry and lay them on top of each other.
First cut into strips, then into cubes. Clean the leek, wash thoroughly and cut into rings. Sauté the smoked pork loin in the frying fat. Add the leek and fry until transparent. Add the lentils. Deglaze with a good 1/4 litre of water and bring to the boil.
Stir in the stock and simmer for about 10 minutes. Wash the basil and cut into strips. Season lentils with salt, pepper, 1 pinch of sugar and balsamic vinegar. Serve with ciabatta and sprinkle with basil.