Step 1

In the bowl of a stand mixer or large bowl, whisk together both flours, the sugar, baking powder, salt and baking soda. Add the spices, if using, and whisk them into the dry ingredients. Add the butter, toss it to coat with the dry ingredients, then place the bowl in the freezer until the butter is well-chilled, 10 minutes.

Step 2

Meanwhile, in a large liquid measuring cup or small bowl, whisk together the cream, buttermilk, crème fraîche, honey, sourdough starter and citrus zest. Keep the liquid ingredients cold in the refrigerator until you’re ready to use them. Line a large baking sheet with parchment paper.

Step 3

Place the bowl of dry ingredients and butter on the stand mixer fitted with a paddle and beat on low speed until the butter breaks down to the size of peas, 1 to 2 minutes. (Alternatively, use your fingertips to smash the butter into the dry ingredients repeatedly until the butter breaks down to the size of peas.) Pour in the chilled liquid ingredients and use a fork to gently stir together the two mixtures until they form large clumps of dough. If adding any fresh, frozen fruit or dried fruit, or swirling in jam (see Variations below), stir it in now to evenly mix.

Step 4

Scrape the dough onto a lightly floured work surface and shape with your hands into a 7-inch-diameter disk, 1 ½ inches thick. Cut the disk into 8 wedges, then arrange the wedges on the prepared baking sheet, spaced evenly apart. Freeze the scones on the baking sheet for at least 30 minutes.

Step 5

When ready to bake, arrange an oven rack in the center of the oven and heat to 400 degrees. Brush the dough wedges with buttermilk and sprinkle liberally with sugar. Place the baking sheet in the oven and bake, rotating the sheet halfway through baking, until the scones are deep golden brown on the outside, 30 to 32 minutes. Transfer the baking sheet to a wire rack and let the scones cool completely before serving. Adapted from Catalina Flores, head pastry chef of Sqirl.

Step 6

In a small bowl or plastic container, whisk together the cream and buttermilk. Cover with its lid or a sheet of plastic wrap. Let sit in a dark place at cool room temperature for 2 to 3 days to allow the cream to ferment.

Step 7

Transfer the crème fraîche in its container (or, if using a bowl, pour it into a glass jar with a lid) to the refrigerator and store for up to 2 weeks.