Mix the curry powder and 1 teaspoon of salt together. Season the fish with the curry salt and a good twist of black pepper. Heat 1 tablespoon olive oil in a non-stick overproof frying pan, then add the fish and 20g of butter. Cook over a medium heat until the fish is golden brown, then turn it over and put the pan into the oven for approximately 3 minutes. Remove, squeeze over the lemon juice and set aside to rest.

Wash and clean the mussels. Melt 20g of butter in a large saucepan, then add the shallots and cook out until they are soft and transparent. Add the bay leaf, thyme and tarragon. Add white wine and bring to the boil, then add cleaned mussels and cover with a lid.

Once the mussels have opened, pour them into a colander over a bowl and leave to drain (discard any mussels that have not opened). Pour the cooking liquid back into the saucepan, add a pinch of saffron strands, the cream and the fish stock. Bring to the boil, then whisk in the remaining butter and simmer until reduced to a creamy consistency. Add a teaspoon of grain mustard, season with salt and pepper and finish with chopped tarragon.

Briefly reheat the monkfish in the over for a few minutes, then remove and transfer to your serving plates. Pour the cooked mussels over the top (in or out of the shell, as you wish) and spoon over the sauce.