Cook the onions in the oil in a skillet until barely wilted. Do not brown. Add the garlic, thyme, parsley, bay leaves, Tabasco to taste, vinegar and white wine. Season with salt and pepper. Simmer for fifteen minutes.
Oil a shallow baking dish large enough to accommodate the fish fillets without overlapping. Arrange the fillets on the dish and spoon the hot sauce over. Sprinkle with additional salt and pepper. Arrange the lemon slices and carrots neatly over the fish. Bring to a boil.
Cover the dish with aluminum foil and place it in the oven. Bake for twenty to twenty-five minutes, depending on the size of the fish. Remove from the oven and chill.