Preheat oven to 375°F. Using a knife, core apples half way through leaving bottom intact.
Place apples in a baking dish and fill center of apple with cranberries (or cherries) and walnuts. Dot with a pat of butter on each apple.
Pour liquid into bottom of pan and insert a cinnamon stick in each apple.
Bake for 50 minutes to an hour.
Mix kefir, cinnamon, and maple syrup together in blender or with wire whisk.
Let apples cool for a few minutes till warm and not hot, then fill apples with kefir and serve.