Rhubarb Cobbler

Preheat the oven to 400 degrees F (200 degrees C). Lightly grease a 9-inch square baking dish.

To make the filling: Mix sugar and cornstarch together in a large saucepan. Stir in rhubarb and water. Bring to a boil; cook and stir for 1 minute. Transfer to the prepared baking dish. Dot with butter and sprinkle with cinnamon.

To make the topping: Sift together flour, 1 tablespoon sugar, baking powder, and salt in a medium bowl. Cut in butter with 2 knives or a pastry blender until mixture resembles coarse crumbs. Beat together milk and egg in a small bowl; add to flour mixture all at once and stir until just moistened.

Drop spoonfuls of topping over rhubarb filling. Sprinkle with remaining 2 tablespoons sugar.

Bake in the preheated oven rhubarb is bubbling and topping is crisp and lightly browned, about 20 minutes.