Heat sugar, strawberries, and lemon juice in a saucepan until the sugar melts.
Boil the mixture for 4-10 minutes until it reaches 105°C on a thermometer.
Cool slightly, skim off froth, and transfer to sterile jars.
Preheat oven to 220°C and grease a large baking tray.
Sift flour, baking powder, and salt into a bowl and rub in the butter.
Stir in the sugar, sultanas, and two beaten eggs.
Gradually stir in the milk to form a smooth dough.
Roll the dough on a floured surface to 2cm thickness.
Cut out scones with a 5cm pastry cutter without twisting.
Brush the tops of the scones with the remaining beaten eggs.
Bake for 10-12 minutes until golden-brown.
Serve warm scones with jam and clotted cream.