In a large mixing bowl combine the flour, granulated sugar, baking powder, and salt. Add in the cold, cubed butter and use your hands or a pastry cutter to cut in the butter until pea sized amounts of butter remain.

Create a well in the center of the flour mixture. Add the buttermilk, vanilla extract, and egg. Use a spatula to gently combine until the dough is thick and sticky.

On a silicone mat or kitchen counter, gently knead the dough, until all the flour is incorporated. Add 1-2 tbsp of flour if the dough is too sticky. Add 3/4 cup of the blueberries, gently folding them in to incorporate. 

Form the dough into a 7-8 inch disc that is about 1 to 1 &1/2 inches tall. Press the remaining 1/4 cup blueberries on the outside of the dough. Use a knife or pizza cutter to cut the scones into 8 equal wedges.

Place the scones 2-3 inches apart on a baking sheet that’s lined with a silicone mat. 

Refrigerate the scones for 20 minutes. The last 5 minutes, preheat the oven to 400º F. 

Brush the tops of the scones with buttermilk or heavy cream. Add course sanding sugar if desired.

Bake for 22-26 minutes or until the scones are lightly golden. Allow the scones to cool.