Preheat oven to 425 F. Generously grease a 12 count cupcake tin
Add raisins to a medium heatproof bowl. Add enough hot water to cover the raisins and allow to soak for 15 minutes. The raisins will plump up. Drain the raisins and discard the excess liquid
In a large bowl, sift together the flour, sugar, baking powder, baking soda, and salt. Add the cold, cubed butter, using your fingers to work the butter into the dry ingredients until it resembles coarse crumbs
Stir raisins into the flour mixture. Add buttermilk and cream. Using your hands, gently scoop and fold the dough until it just comes together
Using 2 spoons, scoop and scrape the dough evenly between the 12 cups
In a small bowl, mix the egg yolk with 2 tablespoons heavy cream. Brush over each scone. Bake until golden brown for 22 - 25 minutes
Serve warm with a slit partially cut down the middle with a pad of Kerrygold butter, blackberry jam, and a sprinkle of flaky sea salt