4 cups sliced fresh or frozen rhubarb (1-inch pieces)
1 large apple, peeled and sliced
1/2 cup packed brown sugar
1/2 teaspoon ground cinnamon, divided
1 tablespoon cornstarch
2 tablespoons cold water
8 macaroons, crumbled
1 tablespoon butter, melted
2 tablespoons sugar
Vanilla ice cream, optional
In a large cast-iron or other ovenproof skillet, combine the rhubarb, apple, brown sugar and 1/4 teaspoon cinnamon; bring to a boil. Reduce heat; cover and simmer until rhubarb is very tender, 10-13 minutes. Combine cornstarch and water until smooth; gradually add to the fruit mixture. Bring to a boil; cook and stir until thickened, about 2 minutes.
In a small bowl, combine the crumbled cookies, butter, sugar and remaining cinnamon. Sprinkle over fruit mixture.
Broil 4 in. from the heat until lightly browned, 3-5 minutes. If desired, serve warm with ice cream.