First, catch your escaped salmon.

Farmed salmon is either the best thing you can eat, or environmentally unsound depending on who you ask. Something about encroaching on unfarmed fishes' territory, or their residue spoils the water for the natives, or the farmed fish can escape. In the past a riposte such as the W. C. Fields quote about fish could blow these nonsensical theories out of the water but today any rational reply is met with a sanctimonious gaze through eyes that are slightly unsteady.

Salmon with beurre blanc.

The sauce
Reduce 3/4 white wine to 1/4 white vinegar in a pan with a sprig of tarragon, a bay leaf, ten black peppercorns and a chopped spring shallot. Cool and strain. Place two tablespoons of this reduction into a pan with a tablespoon of cream. Reduce this by half and then gradually whisk pieces of cold, diced butter until thickened slightly. Add the juice of half a lemon, salt and pepper.

The fish
Cook salmon fillets gently in a pan with a little butter and lemon juice.

The vegetable
Cut four peeled waxy potatoes into half-centimetre slices, boil gently until just soft.

Layer potatoes on serving plates, salmon on top, beurre blanc over.

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There is great pleasure in being on the sea, he thought, in the unknown and the wild suddenness of a great fish; and there is satisfaction in conquering this thing which rules the sea it lives in.

- Hemingway