Preheat your oven to 375°F (190°C). Line a baking sheet with parchment paper or spray it with cooking spray.
In a shallow dish, combine the breadcrumbs, Parmesan cheese, garlic powder, Italian seasoning, salt, and black pepper.
In a large mixing bowl, beat the eggs. Set up a breading station with the flour in one dish, the egg mixture in the next, and the breadcrumb mixture in a third dish.
Pound the chicken breasts to an even thickness (about ½ inch) for even cooking. Season each breast lightly with salt and pepper.
Dredge each chicken breast in flour, shaking off excess, then dip into the egg mixture, allowing excess to drip, and finally coat in the breadcrumb mixture, pressing gently to adhere.
Place the breaded chicken on the prepared baking sheet. Spray the tops lightly with cooking spray.
Bake in the preheated oven for about 20-25 minutes, or until the chicken is cooked through and golden brown.
While the chicken bakes, combine marinara sauce and heavy cream in a frying pan over low heat, stirring until heated through.
Once the chicken is done, remove it from the oven and drizzle the creamy marinara sauce over the top.
Garnish with fresh parsley, if desired, and serve immediately.