Rinse the chicken breasts, pat dry, then butterfly and cut in half. You will have 6 pieces. Set aside. Put the beaten egg in a shallow dish. In a second shallow dish, whisk together flour and 1/2 teaspoon salt. In a third shallow dish, stir together breadcrumbs, Parmesan cheese, Italian seasoning, garlic powder, and remaining 1/4 teaspoon salt.
Working with one chicken piece at a time, dredge all sides first in the flour, shaking off any excess. Next, dip them in the beaten egg, coating all sides and letting any excess drip off.
Dredge each chicken piece in the breadcrumb mixture, coating well on both sides and pressing gently to ensure the crumbs adhere.
Place in a single layer on a cookie sheet. Refrigerate for at least 20 minutes and up to 1 day.
Preheat oven to 375 degrees F.
In a large skillet (preferably cast iron), heat oil over medium heat. Add chicken in a single layer and cook until golden brown – around 2 to 3 minutes per side. (I do it in two batches.) Drain on paper towels.
Lightly oil a baking dish large enough to hold breasts in one layer, and add the chicken in one layer. Spoon 1/4-1/3 cup of the marinara sauce over the top of each breast. Sprinkle shredded Mozzarella cheese evenly over each piece.
Bake, uncovered, for 15-20 minutes; the cheese should be melted, and the chicken should register 165 degrees F on an instant-read thermometer.
While the chicken bakes, cook the pasta (per package instructions) and warm the remaining marinara sauce.
To serve: divide cooked pasta evenly between 6 dinner plates. Top with a piece of chicken, then spoon a little sauce over the pasta surrounding it. Can also be served on a large platter. Garnish with freshly grated Parmesan and chopped basil. Pass the remaining warmed sauce on the side.