Chop the onion and add to a casserole dish with 1 tablespoon of the olive oil and put onto a medium heat. Cook for a couple of minutes, then add the chopped garlic and thinly sliced courgettes.
After 2-3 minutes (stirring regularly), add the red wine and let it bubble down, then throw in the chopped tomatoes.
Allow to cook on the medium heat for 15-20 minutes, until the veg are cooked through. Towards the end of the cooking time, add the chopped basil and season.
Put a frying pan on a high heat with the remaining olive oil. Season the skin of the fish and then put in the pan, skin down. Sizzle skin side down for 3-4 minutes, then turn the fillets over, turn the heat off and leave in the pan for 30 seconds to cook through.
To serve, place the fillets on top of a generous serving of ratatouille, then top with a slice of the goats cheese.