1. Preheat oven to 400 degrees and grease or spray baking sheet with non-stick oil.
2. In a large bowl, combine the bran, flour, sugar, baking powder, and cream of tartar, then cut in the butter with pastry cutter or two forks.
3. In separate bowl, put the eggs, yogurt, and vanilla extract and whisk together until well combined.
4. Stir wet ingredients into dry ingredients, then carefully fold in the fresh blueberries.
5. On a clean surface dusted with flour, put the mixture and carefully push and knead dough until you get a circle, about 9 to 10 inches, then set on prepared baking sheet. With sharp knife, cut dough into wedges.
6. Bake in preheated oven at 400 degrees for 20 to 22 minutes or until golden brown. Remove and cool on rack, then divide at previously cut marks into wedges.