In a mixing bowl, whisk the flour, sugar, salt, and baking powder together.
Cut cold butter into small cubes and toss into flour mixture
Cut the flour into the butter using a pastry cutter or two knives until the mixture comestogether in pea size crumbs. You can also do this step in a food processor.
Add blueberries and toss.
Add the starter, egg, vanilla extract, and heavy cream and use a spoon or fork to gentlymix.
Once the dough has come together, dump onto a piece of parchment paper and use yourhands to press and shape the dough into a disc shape. It’s important to make the disc ofapproximately 5 inches wide.
Cover the dough and place in the freezer for 30 minutes to chill.
Take out and cut into 8 wedges. Arrange onto a parchment lined baking sheet.
Brush the tops of the scones with heavy cream and bank at 400°F (204°C) for 20-25minutes or until the scones are golden brown
Prepare the glaze by whisking together both ingredients. Drizzle on top.