Enjoy the last of summer’s stone fruit in this comforting dessert that’s topped with a delectably crunchy mixture of walnuts and brown sugar.
1. Preheat oven to 375°F. Pit the peaches and plums and cut into thin wedges. In a 12-inch nonstick skillet, combine peaches, plums, ½ cup brown sugar, ½ tsp cinnamon, and pinch of salt. Cook 6–8 min. on medium, until fruit softens, stirring often.
2. Remove skillet from heat. Stir in the cornstarch and extract. Transfer to a 3-qt baking dish.
3. In a large bowl, combine the flour, remaining ½ cup brown sugar, ¼ tsp cinnamon, and ⅛ tsp salt. Add the butter and, with hands, pinch butter into sugar mixture until clumps form. Add the walnuts and continue squeezing mixture together until crumbs form in various sizes. Freeze 15 min. or up to 2 days.
4. Sprinkle crumb topping all over fruit. Bake 35 min., until topping is golden brown and fruit is bubbling. Let cool 10 min. before serving.
Upgrade this dessert by serving it à la mode with vanilla or butter pecan ice cream.