For the jam, heat the sugar, strawberries and lemon juice in a large saucepan over a medium heat until the sugar has melted.
Bring the mixture to the boil and cook for 3-4 minutes (or up to 10 minutes if you prefer a thicker style jam). Check the temperature with a sugar thermometer; it should reach 105C/220F.
Leave the jam to cool slightly and skim off any froth with a clean spoon. Spoon the jam into sterile jam jars, seal and label.
For the scones, preheat the oven to 220C/450F/Gas 7. Grease a large baking tray.
Sift the flour, baking powder and salt together in a bowl, then rub in the butter until the mixture resembles breadcrumbs.
Stir in the sugar, sultanas and eggs.
Stir in the milk with a wooden spoon, a little at a time, to form a smooth dough.
Roll the dough out onto a lightly floured work surface to a thickness of 2cm/¾in.
Dip a 5cm/2in pastry cutter into a little flour and cut out the scones (be careful not to twist the cutter as it will cause the scones to rise unevenly).
Beat the two remaining eggs in a bowl and carefully brush the tops of the scones, taking care not to let any run over the edge.
Place the scones onto the baking tray and bake in the oven for 10-12 minutes, or until golden-brown.
Remove the scones from the oven and allow to cool slightly. Serve the warm scones with the strawberry jam and clotted cream.