Bake garlic and lasagna according to package directions for lasagna.
Squeeze pulp from garlic cloves into a small saucepan.
Add butter, and cook over medium heat until melted.
Whisk in flour, and cook, whisking constantly, 1 minute. Gradually add chicken broth and whipping cream, and cook, whisking constantly, until mixture is thickened and bubbly. Spoon over lasagna, and sprinkle with cheese.