Spinach Artichoke Baked Chicken

Name: Spinach-Artichoke Baked Chicken
Ingredients: 1 (14-ounce) can or jar artichoke hearts packed in water; 4 ounces cream cheese; 8 ounces sour cream; 2 cups baby spinach (about 2 ounces); 1 1/2 cups shredded Italian-blend cheese (4 ounces), divided; 1 teaspoon Dijon mustard; 1/2 teaspoon garlic powder; 2 pounds boneless skinless chicken breasts (about 4); 1 teaspoon kosher salt; 1/4 teaspoon freshly ground black pepper