Position racks in middle and upper thirds of oven; preheat to 425 degrees F. Line 2 baking sheets with parchment paper.Advertisement
Whisk all-purpose and whole-wheat flours, 1/2 cup sugar, baking powder, salt and baking soda in a large bowl.
Make a well in the flour mixture and crack egg in the center. Add sour cream, 1 cup milk, butter, oil, orange zest and vanilla. Using a fork, mix together quickly until everything has just come together but is not overmixed. Using a spatula, fold in nectarine.
Turn the dough out onto a lightly floured surface. Form into 2 balls and pat each into a 7-inch circle about 1 inch thick. Brush with the remaining 2 teaspoons milk and sprinkle with the remaining 2 teaspoons sugar. Cut each round into 8 wedges, separate and place on the prepared pans.
Bake the scones, swapping pans from top to bottom and front to back after 10 minutes, until golden brown, 20 to 25 minutes total.
Tip: To avoid the risk of a metallic taste, recipes that use more than a few teaspoons of baking powder often call for an aluminum-free version of the leavening agent. It can be found in the baking section of well-stocked markets.
To make ahead: Store airtight for up to 1 day; reheat at 300 degrees F for 10 to 15 minutes.
Equipment: Parchment paper
2 fat, 1 1/2 starch, 1/2 other carbohydrate