2 cups all-purpose flour (2 x 128g)
1/3 cup sugar, plus more for dusting
1 teaspoon baking powder
1/4 teaspoon baking soda
1/2 teaspoon salt
8 tablespoons unsalted butter, cold and cut into small pieces
1/2 cup sour cream
1 large egg
1 tsp ground cinnamon
Water: 1 cup = 236 grams
Milk, non-fat: 1 cup = 245 grams
Sugar: 1 cup = 200 grams
1/2 Batch
128g cups all-purpose flour
33g sugar
1/2 teaspoon baking powder
1/8 teaspoon baking soda
1/4 teaspoon salt
4 tablespoons unsalted butter, cold and cut into small pieces
1/2 tsp ground cinnamon
62g milk
1 large egg
Adjust oven rack to lower-middle position and preheat oven to 400 degrees F.
In a medium bowl, mix flour, 1/3 cup sugar, baking powder, baking soda, salt and cinnamon. Add the pieces of diced butter and combine, with your hands, until the mixture resembles coarse bread crumbs.
In a small bowl, whisk sour cream and egg until smooth. Using a fork, stir sour cream mixture into flour mixture until large dough clumps form. Use your hands to press the dough against the bowl into a ball. (The dough will be sticky in places, and there may not seem to be enough liquid at first, but as you press, the dough will come together.)
Place on a lightly floured surface and pat into a 7- to 8-inch circle about 3/4-inch thick. Sprinkle with approximately 1 1/2 tsp. of sugar. Use a sharp knife or pizza cutter to cut into 8 triangles; place on a cookie sheet (preferably lined with parchment paper), about 1 inch apart.
Bake until golden, about 15 to 17 minutes. Cool for 5 minutes and serve warm or at room temperature.