Preheat your oven to 425°F and lightly grease a 12-cup muffin tin with butter or cooking spray. While the oven heats, cut the cold butter into small cubes and place it in the freezer for a few minutes—keeping it very cold is crucial for creating those tender, flaky scone layers. Measure out all your dry ingredients and the liquids so everything is ready to go when you start mixing.

In a large bowl, whisk together the flour, sugar, baking powder, baking soda, salt, and nutmeg until evenly combined. Add the cold butter cubes and use your fingertips to rub the butter into the flour mixture, working quickly and gently until it resembles coarse sand with some pea-sized butter pieces still visible. This technique keeps the butter cold and creates pockets that produce tender, flaky scones. I like to work over a cool surface to keep everything as cold as possible.

In a small bowl or measuring cup, stir together the buttermilk and cream until combined. Create a well in the center of your flour mixture and pour in the buttermilk-cream mixture. Using a wooden spoon or your hands, gently fold and mix until a shaggy dough just comes together—do not overmix, as this will toughen the scones. Fold in the raisins with just a few gentle turns until they're distributed throughout.

Divide the scone dough evenly among the 12 prepared muffin cups, filling each about two-thirds full. The dough will be slightly sticky and rustic-looking, which is exactly what you want. I find it helpful to use a small ice cream scoop to keep the portions consistent, ensuring even baking.

In a small bowl, whisk together the egg yolk with 3 tablespoons of cream until well combined. Brush this egg wash generously over the top of each scone, which will give them a beautiful golden-brown exterior. Place the muffin tin in the preheated 425°F oven and bake for 22 to 25 minutes, until the scones are golden brown and a probe thermometer inserted into the center reads 190°F. They should smell wonderfully buttery and toasted.

Allow the scones to cool in the muffin tin for 5 minutes, then carefully turn them out onto a wire rack or serve them directly from the tin while still warm. The warm scones are best enjoyed topped with a generous dollop of butter and your favorite berry jam. These are perfect served warm with a cup of tea or coffee.