Heat 1 tablespoon of the olive oil in a 12-inch skillet over medium-high heat. While the oil heats, season both sides of the chicken with salt and ground black pepper.
Add the seasoned chicken to the skillet and cook for 3 to 5 minutes on each side or until browned. There should be no pink on the inside, and the internal temperature should reach 165 degrees Fahrenheit. Remove the chicken from the skillet and set aside on a plate.
Add the remaining 1 tablespoon of olive oil to the skillet and add the diced onion and minced garlic. Cook over medium heat for about 2 minutes, until the onions are tender.
Add the tomato sauce, heavy whipping cream, grated parmesan cheese, and Italian seasoning to the skillet and stir to combine. Bring to a simmer over medium heat.
Add the chicken back to the skillet. Top with shredded parmesan cheese and cover with a lid for a minute or two, just until the cheese has melted. Serve over pasta if desired.
