Preheat oven to 350℉.

In a medium sauce pot, heat the 1 tablespoon olive oil over medium-high heat. Add the onions and garlic, and cook for about 3 to 5 minutes, stirring often, until soft and just beginning to caramelize. Season with 1/2 teaspoon salt, 1/2 teaspoon black pepper and the crushed red chili flakes. Stir in the crushed tomatoes and tomato paste and bring to a boil. Reduce heat to low and simmer, covered, for about 15 minutes. Stir in the fresh basil, season with remaining salt and pepper, and set aside.

Season the chicken with salt and pepper. In a shallow baking dish, whisk the eggs. In a separate baking dish, combine the panko, plain bread crumbs and parmesan cheese. Prepare the chicken by dipping it first into the eggs and then into the bread crumbs, patting them onto the chicken to ensure an even coating. Transfer to a wire rack set over a baking and sheet and allow to sit for about 5 minutes.

Heat about 3 tablespoons olive oil in a skillet over medium-high heat. Frying about one or two pieces of chicken at a time, depending on the size of your skillet, cook the chicken for about 3 to 4 minutes on the first side, or until golden brown and crispy. Flip over and continue cooking for about 2 minutes longer. Place the chicken on a wire rack set over a baking sheet and continue frying the rest. Once all done, place in the oven and continue cooking for about 5 to 8 minutes, to cook through. Remove from oven and grate a bit of parmesan cheese on top of the chicken. Set aside.

Cut the loaf of bread into four pieces, then split each piece in half. Place cut side up on a baking sheet and drizzle with remaining tablespoon olive oil. Bake for about 5 to 8 minutes or until golden brown around the edges and crusty. Remove from oven and immediately rub the bread with garlic cloves.

To assemble sandwiches, spoon a few tablespoons of marinara on top of each chicken piece. Top with shredded mozzarella and bake until the cheese has melted, about 5 minutes. Spread a bit of marinara onto each bread half and then place the chicken on top. Sprinkle with fresh basil and then sandwich together. Serve immediately, warm or at room temperature. Enjoy!