Combine Dry Ingredients: In a large bowl, whisk together the flour, baking powder, kosher salt, and sugar, or sift them together to remove any lumps.
Cut in the Butter: Add the cold, cubed butter to the flour mixture. Use your fingertips in a finger-snapping motion or a pastry blender to work the butter into the flour until the mixture has a fairly uniform texture with no large pieces of butter remaining. A food processor may also be used for this step. Add Wet Ingredients: Whisk the egg and cold heavy cream together, then pour the mixture into the flour and butter mixture.
Form the Dough: Gently stir until most of the dry ingredients have been incorporated. Do not overmix; a few dry pockets of flour may remain at the bottom of the bowl.
Transfer the Dough: Turn the entire mixture, including any dry bits, onto a lightly floured counter.
Gather the Dough: Use your hands to bring the dough together, kneading as little as possible to avoid overworking it.
Roll or Pat the Dough: Pat or gently roll the dough to approximately ½ to ⅔ inch thick.
Cut the Scones: Use a 2 to 2½-inch fluted cutter, biscuit cutter, or cookie cutter to cut the dough into rounds. Press the scraps together gently and cut additional scones from the remaining dough.
Chill the Scones: Arrange the cut scones on a parchment-lined baking sheet and place them in the freezer while the oven preheats.
Preheat the Oven: Heat the oven to 425°F while the shaped scones chill.
Brush the Tops: Once the oven reaches 425°F, remove the scones from the freezer and lightly brush the tops with extra cream, or use an egg wash made by whisking 1 egg with 1 tablespoon of water.
Bake the Scones: Bake for 12–15 minutes, or until the tops are golden brown.
Cool: Leave the baked scones on the baking sheet for at least 10 minutes before serving.
Finish: If desired, dust the cooled scones lightly with powdered sugar.
