Preheat oven to 400°F (204°C). Line a large baking sheet with parchment paper or a silicone baking mat and set aside.
In a large mixing bowl, whisk together the oat flour, erythritol, baking powder, whey protein powder, and kosher salt and mix well.
Add blueberries to the dry ingredients and stir to combine.
In a separate mixing bowl, whisk together the greek yogurt, heavy whipping cream, egg, and vanilla extract until fully combined. Add the wet ingredients to the dry ingredients and stir until just combined - Try not to smash the blueberries in this process. The mixture may feel a little wet, but it’s fine. If it’s too wet to be shaped into a ball, add a small amount of oat flour.
Place the ball of mixture onto a lightly floured cutting board or a flat surface, then flatten it into a 7-inch circle. With a sharp knife, cut the dough into 8 equal-sized pieces (just like a pizza!) and place them on the prepared baking sheet, making sure to leave a little room between each one.
Brush the tops of each scone with a little heavy whipping cream.
Bake at 400°F (204°C) for 10-15 minutes or until the tops of the scones are lightly browned and cooked through.
Remove from the oven and allow to cool completely.