Heat the olive oil in a large sauté pan over medium heat. Add the onions and sauté for 4 minutes or until translucent.

Add the garlic and continue to cook an additional minute. Add the tomatoes, 4 basil leaves, salt, and pepper. Bring to a boil, reduce to simmer and cook uncovered for 15-20 minutes or until sauce is thick and fragrant. Remove basil leaves and set sauce aside.

Place 3 deep bowls in an assembly line. Whisk the eggs in the first bowl. In the second bowl combine the panko, garlic powder, 1/2 cup parmesan cheese, and 1 teaspoon salt. Place the flour in the third bowl.

Place the chicken breasts between two pieces of parchment paper and with a meat tenderizer or mallet, pound the chicken evenly, about 1/4-1/2 inch thick.

Take a piece of chicken and coat evenly first in the flour, then the egg and finally with the panko mixture. Press the panko onto the chicken for better adherence. Set aside on a plate. Repeat with remaining pieces of chicken.

Preheat the oven to 425°F.

Heat the vegetable oil in a large, deep skillet over medium-high heat. Add the coated chicken and cook 3-4 minutes on each side until golden or internal temperature reaches 165°F.

Remove the chicken to a parchment lined baking sheet and evenly top each chicken breast with 1/2 of the tomato sauce. Divide 1/2 cup parmesan cheese evenly on top of the tomato sauce. Add the mozzarella cheese on top of the sauce and bake for 15 minutes or until cheese is melted and starting to turn golden.

If desired, place under the broiler for 1-2 minutes for extra crispiness, keeping an eye on it to prevent burning.

Serve chicken parmesan on top of cooked spaghetti with remaining sauce on the side.