Add oil to a baking dish, then add the onions and sauté. Add the green bell peppers and cook well with the onions.

Add the tomato sauce and chicken bouillon cube to the onions, stir well, and let the mixture simmer until the sauce thickens.

Fry the potatoes and eggplants, keeping an eye on the sauce as it thickens.

Once the sauce has thickened, add the fried potatoes, fried eggplants, and cooked ground beef to the baking dish.

To make the béchamel, place the ghee (or butter) and flour in a saucepan over heat and mix well until combined. Gradually add the chicken bouillon cube and milk, stirring constantly.

Season the béchamel with white pepper and stir until it thickens, then remove from heat. Add the egg and mix the béchamel sauce well, then pour it over the top of the baking dish.

Bake in the oven until the sauce thickens a bit more and the top is golden brown.