To make the scrolls: Combine all of the ingredients in a large bowl and mix until it comes together. If you have a stand mixer, you can do this using your dough hook. Knead the mixture until it forms a cohesive and smooth dough. Leave the dough in the bowl or stand mixer, cover with a tea towel and leave it in a warm place for at least 1 hour or until the dough doubles in size.
To make the scroll filling: Add all of the blueberries, a dash of water and a few tablespoons of sugar or maple syrup to small saucepan. Bring to a boil for 3 minutes then reduce to medium heat for 5 minutes. Sift in the cinnamon, cornflour and add the vanilla extract. Use a stick blender to roughly blend the blueberries to form a chunky puree. Return the saucepan to the heat and stir until the mixture thickens. Set aside to cool.
Lightly dust a clean surface with flour. Scoop out the dough and use a rolling pin to flatten the dough into a rectangular shape. Spread the majority of the cooled blueberry puree onto the rectangle, leaving some puree left in the saucepan.
Starting from the long side of the pastry, roll the pastry into a tube. Use a sharp oiled knife to cut scrolls out of the pastry. Arrange on a lined baking tray leaving a little space in between each scroll.** Place a tea towel over the scrolls and set aside to rise.
Preheat the oven to 180°C (350°F).
To make the scroll glaze: Add the remaining powdered sugar or a drizzle of maple syrup to the remaining blueberry puree. Simmer the mixture on low heat until it thickens. Use a stick blender to thoroughly blend the puree and set aside.
Bake the scrolls in the oven for 25-30 minutes or until they are slightly golden brown or when you insert a skewer in one of the middle scrolls and it comes out clean.
When the scrolls have cooled slightly, drizzle with the blueberry glaze.
The scrolls are best eaten the day they are baked. Alternatively, store them in an airtight container at room temperature for 1-2 days.