Season chicken with Italian seasoning, salt, and pepper.
Place chicken in a baking dish and cook in preheated oven for about 20 minutes.
Meanwhile, fill a small saucepan halfway with water and bring to a boil. Cook sun-dried tomatoes in the boiling water until soft, 7 to 10 minutes.
Remove the tomatoes from the water and puree in a food processor until smooth.
Heat olive oil and butter in a skillet over medium heat. Cook garlic in butter and oil until garlic turns brown, 3 to 5 minutes. Stir in the cream of chicken soup and milk. Cook 5 to 7 minutes, stirring frequently. Season with Italian seasoning, salt, and pepper. Stir in the pureed tomato and simmer 5 minutes.
Add baked chicken breasts to the pan and simmer until chicken is completely cooked through and juices run clear, about 5 minutes.