For herb butter and gravy Mix parsley, thyme, sage, marjoram, rosemary, and nutmeg in small bowl. Transfer 1/4 cup herb mixture to small bowl; mix in 1/2 cup butter. Combine broth and apple cider in heavy large saucepan. Boil until reduced to 3 cups, about 20 minutes. Pour broth reduction into bowl. Melt remaining 1/4 cup butter in same saucepan over medium-high heat. Add flour; stir 1 minute. Whisk in broth reduction, then cream, Calvados, and remaining herb mixture. Bring to boil; reduce heat to medium-low and simmer until gravy base is thickened and reduced to 2 3/4 cups, whisking often, about 20 minutes. Cool gravy base slightly. (Gravy base and herb butter can be made 2 days ahead. Cover and chill.)
Pour pan juices into large glass measuring cup; spoon off fat from surface. Pour degreased juices into gravy base and bring to boil over medium-high heat, whisking occasionally. Boil until gravy thickens enough to coat spoon and is reduced to 3 1/2 cups, about 15 minutes. Season gravy to taste with pepper.