Roast the pine nuts in a non-fat frying pan over medium heat. Wash the rocket and remove the stems, cut the tomatoes in half. Cut the basil into strips.
Mix the vinegar, sugar, mustard, pepper and salt with the basil and 4 tablespoons of rapeseed oil.
Cut the monkfish fillet into large cubes and fry in 3 tablespoons of rapeseed oil on both sides for about 3 minutes. Arrange on plates with rocket and tomatoes, pour the marinade on top and sprinkle with pine nuts. If necessary, season with a little lemon juice, pepper and salt.