Preheat the oven to 240C/475F/Gas 9. Slash the fish fillets about half way down and stuff with the herbs. Wash the potatoes and slice them lengthways, just under a 1/2-inch thick. Dry them off with kitchen paper and very lightly coat them in olive oil. Mix in half of your finely chopped garlic, season with salt and pepper, then lay them out in one layer on a flat baking tray. It is always helpful to put a bit of greaseproof on the bottom of the tray, rubbed with olive oil. Lay your potatoes out in a thin layer and put it in the oven for around 12 minutes until they are lightly golden and soft. Remove and put to one side. In a pan add the remaining garlic with 2 good knobs of butter and sprinkle with parsley. Now scatter the mushrooms over the potatoes. Place your sea bass fillets on top, cut the lemons in half and place in the tray as well. Now bake in the oven for 12 to15 minutes, depending on the thickness of the fish. Remove the tray, cover the top with foil and let sit for about 5 minutes during which time all the juices will run out onto the potatoes. Serve it with salsa verde and a crisp white wine.
The secret of a good salsa verde is to chop all the ingredients very finely and to use it the same day, as it doesn't tend to keep for long, even in the fridge. A fantastic accompaniment to any grilled meat or fish. Particularly good with sea bass recipe.Finely chop the first 7 ingredients and put them into a bowl. Add the mustard and red wine vinegar then slowly stir in the olive oil. Balance the flavors with freshly ground black pepper and, if necessary, sea salt and a little more red wine vinegar.