Start by preheating your oven to 275°F. Lightly grease a 9x13-inch baking dish with cooking spray. Slice each chicken breast in half horizontally to create thinner cutlets. Pound them gently to an even thickness of about ½ inch. Dip each cutlet in milk, then coat thoroughly with breadcrumbs.
Heat the butter in a large skillet over medium heat. Once melted, place the cutlets in the skillet and cook until golden brown on both sides. This step locks in the chicken’s flavor while giving it a crispy coating. Transfer the cutlets to your prepared baking dish in a single layer. Bake for about 10 minutes to finish cooking while you prepare the sauce.
Use the same skillet to sauté minced garlic for 30 seconds. Add the chicken broth and bring it to a gentle boil while scraping up any browned bits leftover from the chicken. Stir in the heavy cream and simmer for a few minutes. Reduce the heat to low, then mix in the Parmesan, chopped basil, and a pinch of black pepper. Stir occasionally until the sauce thickens to your liking, about 5 minutes.
Bring the chicken out of the oven and check that the internal temperature has reached 165°F. Pour the basil cream sauce generously over the chicken before serving.