01 - 
                Turn the oven on to 425°F and make sure the rack is set in the middle for even cooking.
              
              
              
                02 - 
                In a large bowl, stir the flour, baking soda, sugar, and salt together until blended.
              
              
              
                03 - 
                Rub the butter into the dry mix with your fingertips until it looks like crumbly bits.
              
              
              
                04 - 
                Toss the raisins or currants into the mixture, making sure they're spread out evenly.
              
              
              
                05 - 
                Make a big open space in the middle of the dry ingredients for adding liquids.
              
              
              
                06 - 
                Pour the buttermilk and whisked egg into the space and mix gently with a wooden spoon until it starts getting tough to stir.
              
              
              
                07 - 
                With floured hands, bring the dough together into a rough round shape without kneading too much.
              
              
              
                08 - 
                Sprinkle in more flour gradually if the dough is too sticky to handle, but don't overdo it.
              
              
              
                09 - 
                Move the dough onto a floured countertop and form it into a nice round loaf without overhandling.
              
              
              
                10 - 
                Put the dough on a baking sheet or into a greased cast iron skillet.
              
              
              
                11 - 
                Cut a deep X across the top using a serrated knife. This helps it bake through evenly.
              
              
              
                12 - 
                Bake it in the oven for 35 to 45 minutes until it's golden and sounds hollow when tapped.
              
              
              
                13 - 
                If the top looks like it's browning too much, cover it with foil partway through baking.
              
              
              
                14 - 
                Push a skewer into the middle of the loaf. If it comes out spotless, it's done.
              
              
              
                15 - 
                Let it sit in the pan for about 5 to 10 minutes, then transfer to a rack to cool down entirely before slicing.