Cut the bread slices (approx. 2 per person) into cubes and let them dry in the oven at approx. 100 ° C. Mix the flour and water without lumps.
Dice the garlic and onions and sauté in the butter. Deglaze with milk and bring to the boil with the flour-water mixture so that everything thickens a little. Season to taste with granulated broth and plenty of parsley. Add the toasted bread pieces and serve.
Garlic, broth and parsley are very important for the taste. And of course the milk. My mother always made this soup with stale bread.