Scallop gratins with sea bass, mussels and prawns

Method

1. Heat the oven to 180°C/160°C fan/gas 4. Put the fish stock in a deep, heavy-based frying or sauté pan. Warm gently with the thyme and bay, add a pinch of salt, then lower the sea bass fillet into the stock. Poach for 1-2 minutes, turning over halfway through the cooking time. Remove with a slotted spoon and set aside, then repeat with the scallops. Strain the stock and keep warm to make the sauce.
2. Heat a knob of butter in a medium saucepan that has a tight-fitting lid. Once the butter is foaming, add the shallot and fry for 30 seconds. Add the mussels, stir quickly, then pour in 1 tablespoon of the wine and cover with the lid. Cook for 3-4 minutes, shaking the pan occasionally until the mussels have just opened. Strain in a colander/sieve, making sure you catch and reserve the liquid. Remove the mussels from their shells (discard any that haven’t opened; discard the shells).
3. To make the sauce, melt the 15g butter in a medium pan over a medium heat, then stir in the flour and cook, stirring, for 1 minute. Pour in the remaining tablespoon of wine then, whisking continuously, slowly add the warm fish stock and mussel liquid (be careful not to add any grit) to form a smooth sauce. Simmer for 10 minutes to thicken, stirring occasionally, then stir in the cream and season to taste with a squeeze of lemon juice and salt.
4. Heat an extra knob of butter in a frying pan and add the mushrooms. Add 2 tsp water and juice of half a lemon and cook for 3-4 minutes until soft. Pour any excess liquid into the sauce. Set the mushrooms aside on a plate. Wipe out the pan and heat the clarified butter (see tip), add the panko breadcrumbs and fry for 2-3 minutes until lightly golden.
5. To assemble the gratins, put a little sauce in a scallop shell/ramekin and top with half a scallop, some flakes of sea bass, 2 mussels, 2 prawns and 3-4 mushroom slices. Finish with a covering of sauce and a sprinkle of panko breadcrumbs. Bake for 10 minutes before serving.