I think these big magnificent flat fish are ideal for celebration meals.  A chunk cut through the fish will mean that the flesh is cooked on the bone so you get that wonderful extra moisture and flavour.  It is also such an easy cut to eat as you enjoy the thick flesh from the top of this. Simply lift out the big bone and enjoy the thinner bottom fillet with the soft gelatinous skin.

This quick béarnaise sauce is simple to make; the tarragon, the rich butteriness and the acidity of lemon are a perfect combination.

Serves 4

Ingredients
Pre heat the oven to 250c. Rub the fish well with olive oil salt and pepper. Place on a roasting dish and put in the oven for about 18-20 minutes. You can sprinkle some fresh rosemary over the fish if you wish, this does impart a nice flavour. While the fish is roasting make the sauce by placing a glass bowl on top of a saucepan which is half full of boiling water. Place the egg yolks and vinegar with just a splash of water (the water will make the sauce light and frothy) in the bowl whilst off the heat and whisk together. Place the bowl on the saucepan, which should be at a gentle simmer, and continue to whisk the egg yolks until you have a light bubbly double cream consistency. And again whilst whisking gently add the melted butter in a gentle stream until the sauce thickens. Add the dried tarragon, taste and season, then add just a squeeze of lemon to your taste. You can serve the fish just naked on a plate with a wedge of lemon and a sprig of parsley and serve the sauce separately or you may simply pour it over the fish. Boiled leeks, marrow, spinach and new potatoes make fine accompaniments.
Method
4 chunks or tranches of brill weighing 275 g 10 oz each Rosemary – optional 2 egg yolks 2 tbsp tarragon vinegar 150 g / 5 oz melted butter 1 heaped tbsp dried tarragon Squeeze of lemon juice Olive oil Salt and pepper