Creamy Chicken Pasta Soup

Onion first, in oil, over heat gentle enough that it softens rather than browns hard at the edges — you want it translucent and sweet, not caramelised, because this soup wants a mild background, not a deep roasted one. Garlic goes in after, briefly, because garlic burns in the time onion needs to soften, and burnt garlic is bitter in a way nothing afterwards fixes.

The dried herbs — thyme, rosemary, fennel seed — are there because this is a Sunday-roast-chicken flavour profile moved into a bowl of broth; it's the same herb logic that goes with a roast bird, just simmered instead of roasted. Fennel seed specifically gives a faint aniseed lift that stops the dish tasting like plain chicken soup and nudges it somewhere a bit more savoury-complex. If you haven't got fennel seed, leave it out rather than substitute something stronger — it's a background note, not a structural one.

Two stocks, vegetable and chicken, rather than all chicken: this isn't fussiness, it's dilution and layering. All chicken stock on its own can taste flat and one-note once you've also added a chicken breast to it; the vegetable stock brings a different, slightly sweeter base that keeps the whole liquid from tasting like concentrated chicken and nothing else. If you've only got chicken stock in the cupboard, use it for the whole 1.5 litres — the soup will be a shade richer and a shade less rounded, not ruined.

Courgette and celery are grated coarse rather than diced because grated vegetable cooks through and softens almost as fast as the broth comes to a simmer — no waiting for chunks to catch up, no biting into a hard lump of celery at the table. This is a kitchen shortcut as much as a texture choice: in a home pan without a kazan's steady heat, grating does the work that long, slow simmering would otherwise need to do.

Chicken breast, not thigh: breast is the lean cut, it poaches clean in a light broth without throwing off much fat, and because it's whole it's forgiving of the ten-minute window the recipe gives it. Thigh would work too and is harder to overcook, but it'll cloud the broth with more fat — fine if you don't mind a richer soup, wrong if you want this clean, brothy character.

Pasta shells catch sauce and hold a bit of the cream in their curve — any small shape that does the same job will do; what you don't want is a long strand shape like spaghetti, which fights the spoon. Double cream is the fat that carries flavour and gives the broth body without flour or a roux — some will tell you a soup needs a thickener to feel "proper," but that's for a different kind of soup; here the cream, the starch shed by the pasta, and the Parmesan at the end are doing that job between them. Parmesan freshly grated, not the dried tub kind, because pre-grated Parmesan is often cut with anti-caking starch and doesn't melt into a sauce the same way — it goes gritty instead of silky. Any firm, salty hard cheese that melts without turning oily will substitute, Grana Padano being the obvious stand-in.

Spinach in at the end, baby leaves if you can — they wilt in seconds; mature spinach takes longer and can leave tougher stems behind, so if that's what you've got, strip the thickest stalks first. Basil fresh, torn rather than chopped with a knife if you want to avoid the cut edges blackening on the plate. And the prosciutto — crisped dry in the oven, no oil needed because its own fat renders out and does the crisping — gives you the one bit of texture in the bowl that isn't soft, which is most of why it's there at all.