Rinse and drain minced meat (place in sieve with bowl underneath to ensure all excess water is removed). Set aside.
Rinse and pat dry the eggplants, slice crosswise, place on a large tray lined with paper towels and sprinkle some Kosher salt on eggplants (1/4-1/2 tsp, as needed) and let sit for 25-30 minutes to allow for excess moisture and bitterness to be removed.
In a cooking pot, add 2 tbsp of grape seed oil and heat on medium high heat. Once oil is hot, add the slices onions and saute for 5-7 minutes until translucent. Turn heat to medium, add the sliced garlic cloves, mix well and continue to cook for 3-4 minutes. Now add the tomato paste and 2 tbsp of water and stir to combine. Cook for an additional 2-3 minutes and now add spices (cilantro, oregano, parsley, Kashmiri Lal Mirch, turmeric, black pepper, cinnamon powder and red pepper flakes), mix well to combine all ingredients (add an additional 1-2 tbsp of water to prevent burning of spices) and cook spices for 3-4 minutes. Now add the minced meat and mix very well to incorporate all ingredients, breaking the meat apart as needed and cook for 10-12 minutes until meat changes color. Now turn heat to low, cover pot and cook for an additional 30 minutes (mix in between 2-3 times as needed). Now add the jar of pasta sauce (3/4 of one jar should be sufficient), mix well, cover again and continue to simmer sauce for an additional 20-25 minutes.
While sauce is simmering, parboil the potatoes until 3/4 done (fork can pierce potato with a little pressure). Let cool, then peel and slice potatoes. Set aside.
Preheat oven to 350 degrees Fahrenheit. In a rectangular dish, add the breadcrumbs, cornmeal and spices (garlic/onion powders, black/cayenne peppers and oregano). Mix to combine. In a small bowl, make an egg wash using 2 tbsp water and 2 eggs (whisk to combine). Pat dry each individual slice of eggplant, dip both sides of eggplant slice in egg wash, then evenly coat both sides of each eggplant slice in combined breadcrumbs and place on aluminum foil-lined baking tray sprayed with some cooking spray. Bake for 16 minutes total (carefully flip each eggplant slice after 8 minutes of baking). Remove from oven and allow to cool.
While eggplants are baking, you can make the Bechamel sauce. Heat a sauce pan on medium heat. Add stick of butter and melt. Once butter melts, turn heat to medium low and add 2 tbsp of flour, mix well with whisk and cook to combine for 4-5 minutes, stirring continuously to form a light roux. Now gradually add the hot milk while continuously stirring (use a whisk) and bring the milk to a gentle simmer and continue to whisk until the sauce thickens, about 8-10 minutes. Now add 1/2 cup of the grated Parmesan cheese, Kosher salt, pinch of nutmeg and white pepper powder and mix well and heat through for another 1-2 minutes. Set aside.
In a rectangular baking dish, spray some cooking spray on bottom. Place the baked eggplant slices in a single layer, top with meat sauce and spread evenly, place sliced potatoes in a single layer, add Bechamel sauce and spread with spatula and repeat layers. Place a thick layer of Bechamel sauce as final top layer, sprinkle both Parmesan and Mozzarella cheeses, parsley flakes and paprika. Drizzle grape seed oil on top and seal tightly with aluminum foil. Place a few slits with knife in the foil to allow for steam to vent. Bake in preheated oven (350 degrees Fahrenheit) for 45 minutes until cooked through and cheese is bubbling (I place the dish on a baking tray to catch any drippings and then place in oven). Carefully remove aluminum foil, place dish on top oven rack and continue to bake for 5 minutes to slightly brown the top layer. Remove and let rest for 15 minutes.
Mouthwatering and exquisitely rich Moussaka is now ready to serve. Perfectly delicious as is or with pasta drenched in extra marinara sauce. Enjoy. Nosh Farma'aiye!