Preheat oven to 400℉.
Line a sheet pan with parchment paper.
In a mixing bowl, dump all dry ingredients and mix well.
Take frozen butter and using a cheese grater, grate all the butter into a bowl.
In a separate bowl, mix sour cream or yogurt with 1 egg.
Add egg mixture and butter into a bowl with dry ingredients.
Mixture will quickly become chunky and dough-like.
Fold in blueberries carefully. It’s ok if some blueberries burst.
Take mixture onto a well floured surface and carefully knead the dough until it is all mixed well together.
Make dough into a ball and using a rolling pin, carefully flatten dough into a round shape about 1-1 ½ inch thick.
Cut into 8 triangles and place on a sheet pan leaving room between each piece.
You can sprinkle each piece with some turbinado sugar or regular granulated sugar.
Bake in the oven for 15-18 minutes.
When done, let cool off a bit. Serve warm or at room temperature.
Serve with coffee, tea or a mimosa.
Serve with butter, jelly or jam.
Bom appetite! Enjoy these yummy scones!