Prawn shells and heads simmered into a deep stock with bruised lemongrass, sliced galangal, garlic and kaffir lime leaves, then strained into a Thai red curry broth. The bones of a great curry start here, the kind of stock that elevates the whole dish from the first spoonful.

The shellfish-shell stock is the technique that turns a home curry into restaurant cooking. Where most home cooks throw the shells out, the proper Thai approach is to crush them, brown them hard in oil to release the carotenoids and the brown flavours, then simmer them with aromatics into a deep, orange-tinted stock that carries forward into every step of the recipe.

Bruising the lemongrass (smashing the white inner stalk with the back of a knife or a heavy pan) is the small step that matters. The bruise releases the volatile oils that simmering alone won't extract; without it, lemongrass adds colour but not perfume.

Galangal rather than ginger is non-negotiable. The two roots look similar but taste nothing alike: ginger is sharp and pepper-warm, galangal is camphor-meets-citrus, with a piney edge that's the foundational aromatic of Thai curry pastes. Sourced from any Asian grocer. Fish sauce, palm sugar and lime juice to balance the curry once the stock is built. The kind of small effort that turns a Wednesday-night curry into a Friday-night one.