Coat the casserole with oil, then Add half the amount of the eggplant.
Top the eggplant with a layer of cottage cheese.
Add the rest of the eggplant slices.
Finally, Spread the tomato sauce and walnuts (optional) on top.
Bake in the preheated oven for about 30 minutes until browned and bubbly.
Serve and enjoy hot with Greek tzatziki sauce.