Preheat oven to 170°C
Stew together rhubarb, 150g sugar, cornflour, ginger, 1 tablespoon butter, and water for 5 minutes
Mix self raising flour, 150g butter, and 60g sugar until it resembles breadcrumbs
Top the stewed rhubarb mixture with the crumble mixture
Bake for 35-40 minutes until golden and bubbling
Serve with ice cream or custard
