1Preheat oven to 400. For filling, whisk together apple juice,cornstarch, lemon juice, and ginger in an 8 inch cast iron skillet til cornstarch dissolves.
2Add apples, cranberries, 3/4 cup sugar, the brown sugar and cinnamon; stir to coat. Bring mixture to a boil over medium high heat. Reduce heat to medium and simmer til mixture thickens, 2 to 3 minutes. Off heat, stir in vanilla.
1 cup flour
1/2 cup sugar
1 tsp. baking powder
1/2 tsp. kosher salt
6 Tbsp. cold unsalted butter,cued
1/2 cup chopped walnuts
1 Tbsp. minced lemon zest
1/4 cup boiling water
4For topping, stir together flour, 1/2 cup sugar, baking powder and salt in a bowl. Cut in butter,using a pastry blender til mixture resembles coarse meal. Add walnuts, zest and water; stir just til moistened. Drop dough evenly over fruit mixture. Bake cobbler til filling is bubbly and topping is browned, about 25 minutes. Let cobbler cool on a rack 1 hour before serving.