Add strawberries, lemon juice, and granulated sugar to a large mixing bowl. Stir to combine. Cover and rest in the refrigerator for at least 2 hours until the berries are juicy. You can do this up to 12 hours in advance.
Preheat the oven to 400 degrees F and line a baking sheet pan with parchment paper or a silicone baking mat.
Whisk together the self-rising flour, granulated sugar, and kosher salt in a medium-sized mixing bowl.
Add in the cold, cubed butter. Using a pastry blender or your fingers, rub it into the dry ingredients until the mixture resembles a coarse meal.
Stir in the milk until a very soft dough forms. Be careful not to overwork it, as this can toughen the cake.
Drop the dough in 6 equal portions onto the prepared baking sheet. Lightly pat the dough into 3-inch discs.
Lightly brush the tops with heavy whipping cream and sprinkle the tops with coarse sugar.
Bake the shortcakes in the center of the oven for 15 to 20 minutes or until golden brown. Let them cool on a wire rack.
While the shortcakes cool, add heavy whipping cream and granulated sugar to the bowl of a stand mixer. Mix on high until stiff peaks form.
Slice off the top third of each shortcake and place the bottoms on six dessert plates. Top with 1/3 cup of the prepared berries and juice, plus a spoonful of whipped cream. Cover with the top.
