Heat the oven to 220ºc/200ºc fan/430F and place a lined baking tray in the oven to preheat.
In a large bowl, rub the butter into the flour, salt, baking powder and sugar mixture until breadcrumbs are formed.
Alternatively, tip the flour, salt, baking powder, sugar and butter into a food processor and pulse until it resembles bread crumbs
Add the lemon juice to the dry mixture with the lemon zest
Slowly add the warm milk. Mix in while you add in the liquid as you may not need all of it - you can do this with a spatula, or still in the food processor
Fold/knead through the blueberries until even
Dust the work surface with some flour and tip the dough onto it - fold the dough over a few times so it is smooth but do not over work it
Flatten the dough out until it is about 5cm thick
Dip a 5cm round cutter into the spare flour and cut out the scones
Flatten out the dough again and cut the rest out until the dough is all used up - trying not to over work the dough
Add the scones to the tray and brush the tops with the beaten egg so it's glazed.
Bake in the oven for 10 minutes.
Leave to cool slightly when baked, and enjoy!
Notes
You can add the zest of two lemons to make them even more lemon flavoured if you wish!
You could easily make smaller or bigger scones if you wanted, but adjust the baking times accordingly.
These are best on the day of baking, but they will last for two days after.
I have tried these with frozen blueberries, and in my opinion it doesn't work. They produce too much liquid and ruin the scones.
You could swap the fruit for others, but beware blueberries are quite small and everything else is larger. Keep to the same amount, but chop up the fruit so they're not too big.
I served mine with a dollop of Rodda's clotted cream, and homemade lemon curd.