In a frying pan, sauté the onion cubes in the oil at a low temperature until soft.
Let the milk boil once, pour over the bread cubes, mix briefly and fold in the eggs. Then loosely stir in the diced tomatoes and pecorino, the basil and the diced onion. Season the mixture with salt, pepper and nutmeg (freshly grated) and let it stand for fifteen minutes. If necessary, add a little more seasoning.
Cover each mini mozzarella ball with a little dumpling mixture and form into a smooth, firm dumpling with moistened hands. Cook in salted water just below boiling point for eight to ten minutes.
e.g. as an ingredient in “Clear tomato soup with basil-mozzarella dumplings”.