Eggplant, Potato, Parmesan Casserole

Make Moussaka

Brown some lamb with aromatics
Dice potatoes and par fry
Dice eggplant, salt and let some water leech
Add some tomato sauce to the lamb, add potatoes and eggplant
Make a mornay with Parmesan
Lamb mixture on bottom, mornay on top
Bake till it’s done

Pretty much what Caplerood said, but I use layers of sliced potatoes and eggplant. Both cooked to slightly tender before building the layers and only mix the tomato sauce with the lamb. Layer potatoes, lamb, eggplant and top with mornay and bake until the cheese sauce is browned and bubbly.