1 cup unbleached all-purpose flour
1 cup plain cake flour
2 teaspoons baking powder
1?2 teaspoon baking soda
1 teaspoon granulated sugar
1?2 teaspoon table salt
1?4 pound unsalted butter , chilled, cut into 1/4-inch cubes, plus 2 tablespoons melted
3 tablespoons minced chives
3?4 cup buttermilk or 3/4 cup plus 2 tablespoons plain yogurt
2 – 3 tablespoons buttermilk additional (or milk), if needed
Set rack at middle position and heat the oven to 450°. Mix or pulse first 6 ingredients in a large bowl or the workbowl of a food processor fitted with steel blade. With your fingertips, a pastry blender, 2 knives, or steel blade of the food processor, mix, cut, or process butter into the dry ingredients until mixture resembles coarse meal with a few slightly larger butter lumps. Add the fresh herb(s) of choice and toss lightly to distribute.
If making by hand, stir in buttermilk with a rubber spatula or fork until mixture forms into soft, slightly sticky ball. If dough feels firm and dry bits are not gathering into a ball, sprinkle dough clumps with additional tablespoon of buttermilk (or milk for the yogurt dough). Be careful not to overmix. If using food processor, pulse until dough gathers into moist clumps. Remove from food processor bowl and form into rough ball.
With lightly floured hands, divide dough into 12 equal portions. Lightly bat a portion of dough back and forth a few times between floured hands until it begins to form a ball, then pat lightly with cupped hands to form a rough ball. Repeat with remaining dough, placing formed dough rounds 1 inch apart on ungreased cookie sheet or pizza pan. Brush dough tops with melted butter or milk. (May be covered with plastic wrap and refrigerated for up to 2 hours.) Bake until biscuit tops are light brown, 10 to 12 minutes.