Season the chicken breast with Italian seasoning, garlic powder and salt.
Heat a large skillet with olive oil over medium heat. Once hot place the chicken in a single layer in the pan and cook for 3 minutes per side without moving to create a nice sear. Remove chicken from pan and set aside.Be careful not to overcrowd the pan. Cook the chicken in 2-3 batches if needed to make sure that you are able to have enough space in the pan to get the chicken seared.
Add the pepperoni and fresh garlic to the pan and cook 30-60 second stirring frequently. Then add the tomatoes, Italian seasoning and salt to the skillet and scrape the bottom to deglaze the pan.
Slowly stir in the cream, then add the parmesan cheese. Once combined, add the chicken and juices back into the sauce and simmer until chicken is done measured at 165˚F internal temp.
Turn off the heat, then top the chicken with mozzarella cheese and cover the skillet and let the cheese melt, about 4-5 minutes.