Preheat and prep: Heat the oven to 400°F (200°C). Line a baking sheet with parchment paper. If your kitchen is warm, chill the prepared sheet in the fridge while you mix the dough.

Mix the dry ingredients: In a large bowl, whisk flour, sugar, baking powder, baking soda, and salt. Add the orange zest and rub it gently into the dry mix with your fingertips to release the oils.

Cut in the butter: Add the cold butter cubes. Using a pastry cutter or your fingertips, work the butter into pea-sized pieces. You should still see small, visible bits of butter—this creates flakiness.

Combine wet ingredients: In a small bowl, whisk the buttermilk, egg, and vanilla until smooth.

Add cranberries: Toss cranberries into the flour-butter mixture to coat them lightly. This helps keep them evenly distributed.

Bring the dough together: Pour the wet mixture over the dry. Stir with a fork until a shaggy dough forms. It should look rough and slightly sticky, with no large pockets of dry flour.

Gently shape: Turn the dough onto a lightly floured surface. Pat it into a 7–8 inch (18–20 cm) round, about 1 inch thick. Avoid heavy kneading; a light touch keeps the crumb tender.

Cut the scones: With a sharp knife or bench scraper, cut the round into 8 wedges. Transfer to the chilled baking sheet, spacing them apart. Sprinkle the tops with coarse sugar if using.

Chill briefly (optional but helpful): For taller, cleaner edges, chill the shaped scones in the freezer for 10–15 minutes before baking.

Bake: Bake for 16–20 minutes, until golden at the edges and set in the center. If using frozen cranberries, you may need an extra minute or two.

Cool and glaze: Let scones cool on the sheet for 5 minutes, then transfer to a rack. Whisk powdered sugar with 2 tablespoons orange juice (add more to thin) and zest if using. Drizzle over warm scones.

Serve: Enjoy warm or at room temperature. A pat of butter or a spoon of clotted cream is a nice touch.