A brown Betty is both layered and topped with sweet buttered crumbs, which absorb the fruit juices and help thicken them.
Preheat the oven to 350°F. Have ready an unbuttered 8-inch square baking dish.
Core or pit and slice:
Stir together with a fork in a small bowl:
Whisk together in a large bowl:
Stir the fruit into the sugar and add:
Spread one-third of the crumb mixture evenly in the bottom of the baking dish and distribute half of the fruit mixture over the crumbs. Spread another third of the crumb mixture evenly on top of the fruit and distribute the remaining fruit mixture over the crumbs. Spread the remaining crumbs on top. Cover the dish with foil and bake until the fruit is tender, about 40 minutes. Uncover the dish, increase the oven temperature to 400°F, and bake until browned, 10 to 15 minutes. Serve warm.