Preheat oven to 375 degrees. Line a baking sheet with parchment paper and set aside.
In a bowl, sift dry ingredients - flour, sugar, baking soda, cream of tartar, and salt. Add in the orange zest.
To the large bowl, add the light butter to the dry ingredients and blend with your hands until the flour mixture looks like a course meal. Add in the dried cranberries.
In a separate small bowl, whisk low-fat buttermilk, lightly beaten egg, orange juice, and vanilla extract.
Fold the wet mixture into the dry mix and combine, do not over mix the dough. Form into a ball.
Turn the dough out onto a lightly floured work surface. Press into an 8 inch disk. Disk should be about 1/2 inch thick. Cut into 8 pieces. Arrange on the prepared cookie sheet.
Using a pastry brush, brush scones with the 1 Tablespoon of buttermilk and sprinkle with the turbinado sugar. Bake for about 15 minutes and check scones for a golden brown color.