Pour the vegetable oil into a large cast iron pan.
Heat the oil up over medium heat.
In a large mixing bowl, combine the breadcrumbs, Italian seasoning, seasoning salt, and pepper.
Mix until combined
Set aside the bread crumb mixture.
In another large bowl, crack the two eggs into the bowl and whisk.
Coat the chicken with the eggs and then coat with the breadcrumb mixture.
Make sure the chicken is fully coated.
Carefully place the chicken into the skillet and let cook for 5-8 minutes on each side or until the chicken is done
Remove the chicken and discard all except 1 tbsp of the oil in the pan.
Toss in the onions, cook for 2 minutes.
Add in the garlic, diced tomatoes, spaghetti sauce and spinach into the skillet.
Let sauce heat up for about 7 minutes before placing the chicken back in.
Preheat oven to low broil.
Combine the parmesan cheese and mozzarella cheese in a small bowl.
Top the chicken off with the cheese.
Place in the oven, and let broil until cheese melts.
Serve and enjoy!