In a 2-quart saucepan, reduce the cider to 1/2 cup. Whisk in mustard, cream and milk and reduce to about 2 cups over medium-high heat, or until the sauce thickens. Add the seasoning, set aside to cool and pour into a wide mouth jar.
Dredge chicken in combined flour/salt/pepper. Hat 3 Tbsp oil in a large skillet. Add chicken and saute on one side for about 5 minutes. Turn and saute for 3 to 5 minutes more or until just slightly done. Remove chicken and keep warm.
Meanwhile, core and slice apples into 1/4 inch slices. Add remaining 1 Tbsp oil to pan. Add apple slices and saute for 3 to 5 minutes or until just tender. Remove apples.
Add cider cream sauce to pan and heat while scraping up any little browned bits from the pan bottom. Return chicken to warm sauce for one minute, then top with apple rings. Heat for one minute and serve. Can be held in warm oven or on very low heat for about 10 to 15 minutes.