Start by combining the flour, baking powder, sugar, and salt in a large mixing bowl. Mix well to ensure the leavening and seasoning are evenly distributed.

Grate the frozen butter directly into the bowl using a cheese grater. Once added, gently incorporate the butter into the flour using a pastry cutter, your fingertips, or a food processor until the texture resembles coarse crumbs.

Toss in your desired mix-ins—chocolate chips, berries, or dried fruit—and lightly coat them with the flour mixture. Set the dry mix aside.

In a separate bowl, whisk together the sourdough discard, egg, vanilla extract, and heavy cream until fully combined and smooth.

Gradually fold the wet mixture into the dry ingredients using a spatula or wooden spoon. Mix only until a shaggy dough forms—avoid overmixing to maintain tender scones.

Turn the dough out onto a lightly floured surface and gently pat or roll it into an 8-inch circle, about 1 inch thick. Using a sharp knife or bench scraper, divide the circle into 8 triangular wedges.

Place the scone wedges on a parchment-lined baking sheet, spacing them about 2 inches apart. For optimal texture and a deeper, tangier flavor, refrigerate the dough for at least 30 minutes or up to 3 days.

When ready to bake, preheat your oven to 400°F (200°C). If desired, brush the tops of the scones with heavy cream and sprinkle with coarse sugar for a crisp, golden finish.

Bake in the center of the oven for 20 to 25 minutes, or until the tops are golden and the edges are lightly browned. Allow to cool slightly before serving warm or at room temperature.