Step 1

First, make the tapenade dressing by blitzing all the ingredients in a food processor until you have a smoothish mixture

Step 2

Season to taste, then keep to one side

Step 3

Next, chop the thyme leaves for the bass and mix with the olive oil

Step 4

Season with salt and pepper, then coat the bass fillets all over and leave to marinate while you get the gratin prepared and cooked

Step 5

Preheat your oven to 180C fan/gas mark 6

Step 6

Warm a large frying pan and add the olive oil. Sweat off the shallots, fennel and garlic for 5 minutes, stirring the mixture so that it softens evenly

Step 7

Place the courgettes, tomatoes, creme fraiche and parmesan in a large bowl and then add the shallot mixture

Step 8

Mix everything together well, season to taste and transfer to an ovenproof dish. Place in the oven and bake for 25 minutes

Step 9

Remove the gratin from the oven and place the fish on top. Return the dish to the oven and cook for a further 8 minutes

Step 10

Remove from the oven and sprinkle over the thyme leaves and lemon zest. Serve immediately with the dressing on the side