Dice the onion and eggplant into relatively small dice.

Warm half the oil in a medium skillet/frying pan and add the onion and eggplant. Cook, stirring regularly, until they are both softening. Add a little more oil at a time as needed to avoid sticking (you just don't want all at once or just a few pieces of eggplant will absorb it all).

Once the eggplant and onion are soft, finely chop the garlic and add to the pan. Stir and cook for a couple minutes. Add the leftover lamb and cook a minute, stirring regularly, until it browns.

Add the remaining ingredients to the pan (parsley, mint, chocolate/cocoa if using, oregano, cinnamon, tomatoes and olives). Mix well, bring to a simmer and cook over a low heat for around 10 minutes to bring the flavors together. Serve over pasta of your choice (recommend eg penne, farfalle).