2 cups all purpose flour 1/4 cup granulated white sugar 1/2 teaspoon baking powder 1/2 teaspoon baking soda 1/2 teaspoon salt 1/2 cup (1 stick) unsalted butter, cold and cut into pieces 1/2 cup milk or semi sweet chocolate chips or chunks 1 teaspoon pure vanilla extract 2/3 cup buttermilk Egg mixture for brushing tops of scones: 1 large egg, lightly beaten 1 tablespoon milk sugar, for sprinkling the tops of the scones. Preheat oven to 400 degrees F and place rack in middle of oven. Line a cookie sheet with parchment paper. In a large bowl, whisk together the flour, sugar, baking powder, baking soda and salt. Cut the butter into small pieces and blend into the flour mixture with a pastry blender or two knives. The mixture should look like coarse crumbs. Stir in the chocolate chips. Add the buttermilk and vanilla extract to the flour mixture and stir just until the dough comes together. Do not overmix the dough. Transfer to a lightly floured surface and knead dough gently four or five times and then pat the dough into a circle that is about 7 inches round and about 11/2 inches thick. Cut this circle in half, then cut each half into 3 pie-shaped wedges (triangles). Place the scones on the baking sheet. Make an egg wash of one well-beaten egg mixed with 1 tablespoon milk and brush the tops of the scones with this mixture. Sprinkle with sugar (if desired). Bake for about 20 to 25 minutes or until golden brown and a toothpick inserted in the middle comes out clean. Transfer to a wire rack to cool. Makes 6 scones. Note: Brushing the tops of the scones with the egg/cream mixture helps brown the tops of the scones. Note: If you find the bottoms of the scones are browning too much during baking, use two sheets pans (place one pan inside another). Note: Buttermilk has a nice thick creamy texture with a rich tangy buttery taste that makes baked goods tender. It is now commercially made by adding a bacteria to whole, skim, or low fat milk. However, in the past it was the liquid left over after churning butter. You can make your own by adding 1 tablespoon of white distilled vinegar, cider vinegar, or lemon juice to 1 cup of milk. Let stand 5 to 10 minutes before using.