Step 1

Wash the blueberries and pick over them to make sure you remove any stems etc that may still be attached. Place the blueberries in a saucepan/pot with almost all of the water (save back 1-2 tbsp for later) and the sugar.

Step 2

Place the pan over a medium heat and bring to a boil, stirring now and then so that the sugar dissolves. Once boiling, continue to boil gently for around 15 - 30 minutes, uncovered, stirring occasionally, so that most of the berries become soft and start to break up.

Step 3

While the soup is cooking, add the reserved water to the cornstarch and stir to form a smooth paste.

Step 4

Remove the soup from the heat once the berries are fairly well broken up and it has reduced a bit. If you like, you can use an immersion/stick blender to blend some or all of the soup to be smoother (I quite like to blend some but not all). Off the heat, add the cornstarch slurry and immediately stir to mix it in and ensure it doesn't clump together.

Step 5

Return the soup to a medium-low heat and warm, stirring constantly, for a few minutes to thicken the soup to the consistency you want.

Step 6

You can serve the soup either warm or chilled, as you prefer. In both cases, you can serve as it is or topped with a spoonful of whipped cream.