1tsp potato flour
1 tbsp jelly sugar
Mix flour, sugar and butter into a crumble. Spread half of it in a baking form.
Cover with your blueberries (can be substituted with raspberries, black berries etc.)
Sprinkle over the berries potato flour and jelly sugar and crumble over the remaining crumble.
Bake in the middle of the oven at 225 degrees Celsius for about 15-20 min until you get a nice golden crunch on the top.
I served it with Vanilla ice cream while it was still a bit warm.