Marinade: Combine the marinade ingredients in a bowl. Place the meat in a shallow dish. Pour over the marinade. Leave overnight if possible. Turn occasionally.
Remove the meat from the marinade, put on a baking tray and place in a pre-heated oven, Gas Mark 6, 200°C (400°F).
Allow 16 minutes per kg for rare, 20 minutes per kg for medium. When the meat is cooked, allow it to cool and then cut into slices.
Niçoise Salad: Heat the oil in a large frying pan and fry the aubergine slices on both sides. Remove from the pan.
Add the onion, and a little more oil if necessary, and cook until just soft but not coloured, then add the peppers and cook for 2 - 3 minutes.
Return the aubergine to the pan and add the tomatoes. Gently stir the tomatoes into the mixture.
Turn the salad into a dish, leave to cool, then lightly moisten with some French dressing. Set aside the hard-boiled eggs and black olives for final garnish.