In another bowl, mix the gluten-free flour blend, 1 cup granulated sugar, cinnamon, the beaten egg, and salt until just combined and crumbly. Sprinkle this mixture evenly over the fruit layer.
Place the dish in the oven and bake for 35 minutes, or until the fruit is bubbly and the topping is lightly browned. If desired, serve with a scoop of ice cream or a dollop of whipped cream.