For the jam, heat the sugar, lemon juice and three tablespoons water in a large pan, slowly, until the sugar has melted. Add the strawberries and stir gently. Bring the jam up to the boil and cook for 3-4 minutes or up to 10 minutes if you prefer a thicker jam. Remove from the heat, allow to cool slightly, then pour into sterilised jars and allow to cool completely.
Preheat the oven to 220C/425F/Gas 7.
Sift together the flour, baking powder and salt into a bowl then add the butter and rub into the flour, creating a fine breadcrumb consistency.
Add the sugar and two eggs, lightly beaten, and mix well. Add the milk, a little at a time, working with a wooden spoon to form a smooth dough.
Roll on a lightly floured work surface until 2cm/¾in thick. Dip a 5cm/2in pastry cutter into the flour then stamp out rounds from the dough, using one sharp tap and not twisting the dough as you cut - twisting the scone mix will result in an uneven rising.
Re-roll the leftover dough and cut out more scones until all the dough has been used.
Flip the scones over and place onto a baking tray. Brush the beaten egg yolks over the top of the scones, taking care not to let any run over the edges.
Place the scones on a greased baking tray and bake in the pre-heated oven for 10-12 minutes until golden-brown.
Allow to cool slightly, then serve while still warm with strawberry jam, butter and clotted cream.