Preheat oven to 400°F. Line a baking sheet with parchment paper.
Cut the butter into small cubes and place in the freezer for 20 minutes before using.
Wash the strawberries, remove the stems, and quarter them. Wash the lemon and zest it.
In a bowl, combine the flour, salt, baking powder, sugar, and lemon zest. Add the cold butter and roughly knead everything together until a dough forms. Small pieces of butter should still be visible.
Whisk the buttermilk with the egg and stir the mixture into the dough with a fork. Finally, gently fold in the quartered strawberries, being careful not to crush them.
Place the dough on a floured work surface and shape it into a rectangle with your hands. Cut the dough into 8 equal-sized triangles with a knife.
Place the scones on a baking sheet. Brush them with milk and sprinkle with brown sugar.
Bake the scones for 30 minutes on the middle rack until golden brown.
