01 - Preheat the oven to 425°F. Line a baking sheet with parchment paper, ensuring it's ready for baking.
02 - In a large mixing bowl, thoroughly whisk together the all-purpose flour, granulated sugar, baking powder, and salt.
03 - Add the cold, cubed unsalted butter to the dry ingredients. Use a pastry cutter or your fingertips to cut the butter into the flour mixture until it resembles coarse crumbs.
04 - In a separate small bowl, whisk together the whole milk, the lightly beaten large egg, and the pure vanilla extract until combined.
05 - Pour the prepared wet ingredients into the dry mixture. Stir gently with a spoon or spatula until just combined, being careful not to overmix the dough.
06 - Turn the dough onto a lightly floured surface. Gently pat it into a rectangle approximately 1 inch thick. Using a 2.5-inch round cutter, cut out 6 shortcake rounds, re-gathering and re-patting any dough scraps as needed.
07 - Place the cut shortcake rounds onto the prepared baking sheet. Bake for 15 to 18 minutes, or until the tops are golden brown. Transfer the baked shortcakes to a wire rack to cool completely.
08 - While the shortcakes cool, combine the hulled and sliced fresh strawberries with granulated sugar and the optional lemon juice in a medium bowl. Toss gently to coat and set aside for at least 15 minutes to allow the strawberries to macerate and release their natural juices.
09 - In a chilled large bowl, combine the cold heavy cream, powdered sugar, and pure vanilla extract. Beat with an electric mixer on medium-high speed until soft peaks form.
10 - To assemble, carefully slice each cooled shortcake in half horizontally. Spoon a generous amount of macerated strawberries and their juices over the bottom half of each shortcake. Top with a dollop of fresh whipped cream, then cover with the top half of the shortcake. Garnish with additional berries and cream if desired, and serve immediately for best results.