Combine apples, apple cider, 1 tablespoon brown sugar, vanilla, 1/2 teaspoon cinnamon in a large saucepan over medium-high heat. Cook, stirring occasionally, until apples are tender but not mushy, about 10 minutes. Stir in 1 tablespoon butter until melted, remove from heat and transfer apple mixture to a 9-inch glass pie plate.
Place bread in food processor and process until crumbs are formed, about 15 seconds. Melt remaining 1 tablespoon butter in microwave for 20 seconds. Toss crumbs with melted butter, walnuts, remaining 2 tablespoons brown sugar and remaining 1/2 teaspoon cinnamon. Scatter crumb mixture on top of apples and bake for 30 minutes, until topping is crisped and lightly browned.