Sauté the onions and garlic in 1 teaspoon of olive oil, add the tomatoes, then add the spices: salt, chopped chilli pepper, rosemary, sugar, 1 dash of chilli sauce, 1 dash of lemon juice and a little harissa. A shot of good Italian red wine never hurts (in the dish and for the cook), then cover and let the sauce simmer for about 15 minutes, stirring occasionally. In the meantime, preheat the oven to 200 ° circulating air.
Put the finished sauce in a baking dish, mix in the gnocchi and the diced mozzarella, cover and put the dish in the oven for about 15 minutes. Turn off the oven and leave the mold open in the tube for another 10 minutes.