Preheat your oven to 375°F and position the rack in the upper third.
Cut chicken breasts lengthwise to make four even cutlets. Season both sides with salt and pepper.
In a medium bowl, mix the ricotta, parmesan, garlic, and Italian seasoning until smooth.
Spread half of the marinara sauce into a 9×13 baking dish.
Place the chicken cutlets in the dish in a single layer.
Spread the ricotta mixture evenly over the top of each chicken cutlet.
Spoon the remaining marinara sauce over the chicken.
Cover the dish tightly with foil and bake for 20 minutes.
Remove the foil, sprinkle mozzarella evenly over the top, and bake uncovered for 15 minutes.
If desired, broil for 1–2 minutes to lightly brown the cheese. Watch closely to avoid burning.
Let the chicken rest for 5 minutes before serving. Garnish with fresh basil if using.