For the sauce vierge, heat the oil in a pan, then add the tomatoes, shallots and capers. Season with salt and freshly ground black pepper and gently heat for two minutes, then stir in the lemon juice and chopped herbs.
For the vinaigrette, mix the olive oil, the vinegar, salt and freshly ground white pepper in a bowl. Mix well.
Push the garlic and thyme into a clean glass bottle. Pour the vinaigrette into the bottle.
For the potatoes, gently heat a little vinaigrette in a pan with the potatoes. (The leftover vinaigrette can be stored in the fridge for up to a week.) Crush the potatoes lightly with a fork. Add the black olives and chives to the crushed potatoes and season with salt and freshly ground black pepper.
For the sea bass, heat a little olive oil in a non-stick pan. Score the skin of the sea bass and season the flesh with salt and freshly ground black pepper. Place the fish, skin-side down, into the hot oil. Cook the sea bass for 4-6 minutes on the skin-side according to the thickness of the fish. Turn the fish onto its flesh side briefly to finish cooking it.
To serve, place a metal chef's ring in the middle of each plate and spoon the olive crushed potatoes into the rings. Carefully remove the rings. Take the sea bass off the heat and squeeze over the lemon juice. Place the fish, skin-side up, on top of the potatoes then spoon the warm sauce vierge over and around the fish.