For the pan-fried turbot, dredge the turbot fillet in the flour and shake off any excess.
Heat the olive oil in a frying pan and fry the turbot for 1-2 minutes on each side, or until completely cooked through.
Meanwhile, for the sauce, heat the olive oil and butter in a pan, add the onion and bacon and gently fry for 4-5 minutes, or until the onion is softened and the bacon is lightly browned.
Add the mushrooms and cook for 1-2 minutes.
Add the red wine and fish stock, turn up the heat and simmer until the liquid has reduced by half. Season, to taste, with salt and freshly ground black pepper.
To serve, place the turbot onto a serving plate and pour over the sauce.