Preheat you barbecue grill to high. Pound the thick end of your chicken breasts a bit with a kitchen mallet to make them a uniform thickness, about 1/4 inch thick. Place the pounded breasts in a glass or ceramic dish and pour enough Italian dressing over them to coat. Cover and refrigerate until ready to cook.
Melt 3 tablespoons of butter in a medium saucepan over medium-low heat. Add the minced garlic and sweat it for about 5 minutes making sure the garlic doesn't brown. Add the wine and cook for another 5 minutes. Add the remaining ingredients for the sauce and whisk well until smooth. Bring mixture to a simmer cook until it's thick. You'll be able to draw a line on the back of your spoon. Cover sauce and remove it from the heat.
Cook the penne pasta following directions on the package (7 to 9 minutes in boiling water). Strain pasta and set it aside when it's done. Grill the chicken breasts for 5 to 6 minutes per side. Set aside to rest and then slice each breast into strips.
Preheat the oven to 450 degrees F. In a large, shallow baking dish, pour in all of the cooked pasta. Add the chicken, the chopped prosciutto and all of the Parmesan cream sauce. Toss to coat. Combine 3 tablespoons of grated Parmesan cheese with 1 1/2 teaspoons paprika and sprinkle the mixture over the top of the dish.
Bake for 10 to 12 minutes, or until the top begins to brown. Remove from the oven and let sit for 5 to 10 minutes. Serve with a sprig of rosemary in the center of the dish.