Heat the oil in a saucepan, add the garlic and chorizo and fry gently for 3–4 minutes. Add the wine, stock, tomato purée and sugar, season with salt and pepper and bring to the boil, then reduce the heat and simmer for 5 minutes.
Reduce the heat to a very gentle simmer, then break the eggs, one at a time, into the pan, leaving space between them. Poach for 3–4 minutes until the whites are set and the yolks are cooked to your liking.
Check the seasoning, then transfer 1 egg into the base of each of 4 bowls, ladle over the soup and garnish with a little chopped parsley. Serve scattered with croûtons.