Red Mullet with Beef Marrow

Name: Red Mullet with Beef Marrow (Filets de rouget à la moelle de boeuf)
Prep time: 30 min
Cook time: 10 min
Total time: 40 min
Yield: For four people
Cuisine: French
Ingredients: 20 g (¾ oz) salt-cod salt or coarse salt; 20 g (¾ oz) salt-cod salt or coarse salt; 20 g (¾ oz) salt-cod salt or coarse salt; salt, freshly-ground pepper; salt, freshly-ground pepper; 6 red mullet, weighing 200 g (7 oz) each; 120 g (4½ oz) beef marrow; 3 shallots, finely chopped; a little flour; 120 g (4½ oz) butter; 2½ tablespoons arachide oil; 2 tablespoons fresh tomato sauce; 200 ml (⅓ pint) red Burgundy