Preheat the oven 425° and line a baking sheet with parchment paper.

Weigh the flour into a large mixing bowl, then add the butter and rub it in with your finger tips. The flour should have a sandy consistency, without any large lumps.

Stir in the sugar and salt until they’re mixed in well.

In a liquid measuring cup, measure out the sourdough starter, milk, and whipping cream. Whisk them to combine, then pour the mixture into the bowl with the dry ingredients.

Use a large fork or wooden spoon to stir the dough together, just until all of the flour is incorporated.

Sprinkle the blueberries over the dough, and gently fold them in. Some will burst, but try to keep as many as possible whole to avoid them oozing during baking.

Dump all of the dough out onto the parchment lined baking sheet. With your hands or the back of a wooden spoon, spread the dough into a circle about 10″ across and about 1″ high.

Cut the round of dough into 8ths by cutting it first into halves, then quarters, then eighths. Sprinkle the top generously with 3-4 tablespoons of sugar.

Bake the scones for 24-28 minutes, or until they are golden brown. Separate the tips of the scones gently (and just a tiny bit) to peek in between the edges of the scones and make sure that they aren’t doughy in the center.

Remove the scones from the oven, and allow them to cool for 20-30 minutes. They will have baked together, so re-cut them before serving.