Begin by preheating your oven to 200°C (400°F). Prick the eggplants with a fork, then place them on a baking tray lined with parchment paper. Roast in the oven for 25-30 minutes, turning halfway through, until the skins are charred and the flesh is soft.

While the eggplants roast, heat olive oil in a large pot over medium heat. Add the lamb cubes and cook for 5-6 minutes, searing until browned on all sides. Browning the meat enhances the flavour of the stew.

Add the chopped onion and garlic to the lamb and sauté for another 3-4 minutes until softened and fragrant. Then add the green bell pepper and cook for an additional 2 minutes, stirring to combine.

Stir in the chopped tomatoes, tomato paste, ground cumin, black pepper, and salt. Mix well to coat the lamb in the spices and tomatoes. Pour in the hot water or broth, bring the stew to a gentle simmer, then reduce the heat to low. Cover and let simmer for 40-45 minutes, or until the lamb is tender and the flavours have melded.

Remove the roasted eggplants from the oven and allow them to cool slightly. Once cool enough to handle, peel off the charred skin, and scoop out the flesh. Place the eggplant flesh in a bowl and mash it with a fork or blend for a smoother consistency.

In a separate saucepan, melt the butter over medium heat. Add the flour and whisk continuously for 2-3 minutes until the flour is lightly golden, forming a roux. Slowly pour in the warm milk, whisking constantly to avoid lumps, until the mixture thickens to a creamy consistency.

Add the mashed eggplant to the saucepan, stirring well to combine with the béchamel sauce. Sprinkle in the grated Kasseri or Gruyère cheese, stirring until melted and fully incorporated. Season with salt and pepper to taste. This purée should be smooth and creamy.

To serve, spread a generous portion of the eggplant purée onto each plate, creating a base. Spoon the lamb stew over the purée, letting the sauce cascade around the sides. Garnish with a sprinkle of fresh parsley or additional cheese, if desired. Serve warm with crusty bread or rice to complement the dish's richness.