PREPARATION

Slice the onion and put to fry in a pan with the oil, then add the tomato paste and diluted with 50 grams of water.

Simmer with the lid on for about 10 minutes after adjusting for salt and pepper.

Meanwhile, peel the potatoes and cut into cubes, sliced celery and add both to the sauce with the tomato and cook for another 10 minutes.

Pour 1.2 liters of boiling salted water and cook until the potatoes are almost completely undone.

Apart cut the slices of bread and toast them in the oven or on a grill, then arrange them in a single portion 6 bowls and pour over the boiling soup. Sprinkle with grated cheese and pepper and serve immediately.