Begin by preheating your oven to 425°F.
Heat a large, oven-safe skillet over medium heat. Add 1 tablespoon of olive oil.
Next, combine the Italian seasoning and red pepper flakes in a small prep bowl. Place the chicken thighs in a large bowl and drizzle with the remaining olive oil. Sprinkle chicken with one tablespoon of Italian seasoning/red pepper flake mixture. Season with salt and black pepper, to taste. Toss to evenly coat.
Place the chicken thighs in the hot skillet and cook for 4-5 minutes per side, or until the chicken develops a golden-brown crust.
Remove from heat and add the butter, chicken stock, and cherry tomatoes to the pan. Top each chicken thigh with a slice of fresh mozzarella cheese and sprinkle with remaining Italian seasoning/red pepper flake mixture. Season to taste with additional salt, black pepper, and red pepper, if using.
Next, transfer the skillet into your pre-heated oven and bake for 15-20 minutes, or until your chicken is cooked through (165 degrees Fahrenheit) and the mozzarella is melted.
Remove from the oven and allow the chicken to rest for 5 minutes.
To serve, spoon pan sauce over chicken and top with fresh basil sprigs.