Place the lentils in a large saucepan and cover with water. Add the bay leaf and bring to the boil. Simmer for 30 minutes until just tender. Remove from the heat, discard the bay leaf and add the chopped tomatoes.

Preheat the oven to 200C and brush an ovenproof dish with extra virgin olive oil. Arrange the fish steaks in the dish.

Make the topping: in a small bowl mix all the gremolata ingredients together. Use to top the fish steaks and bake for 15 minutes until the fish is just cooked and the topping is golden. Season the lentils and serve alongside the fish.