Preheat the oven to 150°C.
Smear the lamb flesh with garlic, rosemary, salt, and pepper, then roll and tie with string.
Heat 25g butter and olive oil in a casserole dish and brown the lamb roll for 15 minutes.
Remove the lamb and set aside on a plate.
Sauté sliced onions, fennel seeds, and herbes de Provence in the dish until soft.
Place lamb on onions, add wine, lamb bones, and water to reach halfway up the meat.
Season, cover, and cook in the oven for two hours.
Remove lamb, discard string, wrap in film, and chill in the fridge.
Reduce the braising liquid to 200ml, then strain through a sieve.
Preheat oven to 200°C and bake whole aubergines for 45 minutes.
Discard aubergine skin and roughly tear the flesh.
Fry onions and garlic in oil, then stir in spices for five minutes.
Add tomatoes and cook for 10 minutes.
Stir in aubergine flesh and cook over low heat for 15 minutes.
Combine spinach and sliced preserved lemons in a bowl.
Whisk olive oil, lemon juice, balsamic vinegar, and honey, then toss with the salad.
Unwrap lamb, cut into four, and sear in a pan with 25g butter.
Serve lamb with aubergines topped with kashk and herbs, alongside the salad and yoghurt.