Preheat oven to 425F.
In a large mixing bowl combine the baking mix, sugar and dill. In a small bowl, combine the egg, sour cream and milk. Pull out about a teaspoon of the liquid in a small dish or coffee cup then add the remaining liquid to the bowl of dry ingredients. Give it a gentle stir with a fork or rubber spatula until a soft dough forms.
Sprinkle a little bit of baking mix onto your worktable and turn the dough out onto it. Give it a quick knead, about 10 turns should do the trick. Transfer the dough to a baking sheet and use your hands to shape it into a round that is flat on top and about 8 inches across. Brush the reserved liquid over the top of the dough and cut it into 8 wedges with a long knife. Leave the wedges together, though, you'll break them apart after they've finished baking.
Pop the pan into the oven and bake the scones until the edges are golden brown, 12-15 minutes. Remove from oven and let sit for about 5 minutes. Break the wedges apart and serve with slices of smoked salmon and some additional sour cream.