For a deeper flavor, try substituting 1/3 cup firmly packed dark-brown sugar for the 1/3 cup granulated sugar in the shortcakes. Either variation is best served slightly warm.
Macerate strawberries: Place berries in a bowl; stir in lemon juice and 1/2 cup granulated sugar. Let stand until berries are very juicy, about 1 hour.
Meanwhile, in a large bowl, whisk together remaining 1/3 cup granulated sugar, flour, baking powder, and salt. Using a fork or pastry blender, cut butter into mixture until it resembles coarse meal. Add 2 cups plus 2 tablespoons cream; mix just until dough comes together. Transfer to a lightly floured surface; pat into a 1-inch-thick square. Using a 2 1/2-inch or 1 1/2-inch round cookie cutter, cut out 9 large or 25 small rounds; transfer them to a parchment-lined baking sheet. Cover; refrigerate 20 minutes or overnight.
Preheat oven to 400 degrees. Remove rounds from refrigerator. Whisk together remaining 2 tablespoons cream with egg yolk. Brush tops with egg wash. Sprinkle with turbinado sugar, if desired. Bake until golden brown, 12 to 15 minutes for small shortcakes and 15 to 18 for large. Cool slightly on wire racks, about 15 minutes.
Slice shortcakes open with a serrated knife; place bottom halves on serving plates. Add a dollop of whipped cream and the strawberries with their juice, and top off with matching shortcake halves.