Heat oven to 180C/fan 160C/gas 4.
Check the cod for bones and remove if
necessary. Heat the oil in a flameproof
casserole, add the spring onions, saffron
and garlic, then cook over a low heat for
1-2 mins until soft.
Add the butter beans and stock, then
bring to the boil and season. Nestle the
cod, skin-side up, into the butter beans,
then cover and cook in the oven for
10 mins, or until the cod is just done.
Lift from the oven and check the seasoning.
Add the mint just before serving.
To serve, put 2 slices of toasted baguette
in a bowl, top with butter beans and cod
(pulling away the skin if you want) then
spoon the cooking juices around the fish.
Finish with a dollop of crème fraîche.