Season the chicken breasts with salt, black pepper, and Italian seasoning on both sides.
In a large oven-safe skillet, heat the olive oil over medium heat. Add the chicken breasts and cook for about 5-6 minutes on each side, or until they are golden brown.
Pour the marinara sauce over the chicken, ensuring it's well coated. Spoon half of the cottage cheese on top of the chicken and spread it evenly.
In a small bowl, mix the grated Parmesan cheese and breadcrumbs (if using). Sprinkle this mixture over the cottage cheese layer.
Transfer the skillet to the preheated oven and bake for 20-25 minutes, or until the chicken is cooked through and the topping is golden brown.
While the chicken is baking, sauté the fresh spinach in a separate pan over medium heat until wilted, about 3-4 minutes.
Once the chicken is done, remove it from the oven and let it rest for a few minutes before serving.
To serve, place a generous scoop of sautéed spinach in a bowl, top it with a chicken breast, and spoon extra marinara sauce over the top.