Use any of the following liquids:
Add any of the following to the fish-poaching liquid and simmer for 5 minutes before adding the fish:
- Finely diced onion or shallot, or sliced leeks
- Finely diced carrot, celery, or fennel
- Bay leaf, thyme sprigs, or fennel fronds
- One lemongrass stalk, trimmed and pounded with the spine of a knife until bruised and fragrant
- Crushed black peppercorns
- Strips of lemon or orange zest, removed with a vegetable peeler
- Smashed garlic cloves
- A piece of kombu
- Dried chiles