01 - Preheat oven to 425°F. Line a baking sheet with parchment paper.
02 - In a large bowl, whisk together flour, sugar, baking powder, and salt until well combined.
03 - Cut cold butter into dry mixture using pastry cutter or fingertips until mixture resembles coarse crumbs.
04 - In a small bowl, whisk milk, beaten egg, and vanilla extract. Pour into dry ingredients and stir gently until just combined.
05 - Turn dough onto lightly floured surface. Pat into 1-inch-thick rectangle. Cut into 6 rounds using 2.5-inch cutter, gathering scraps as needed.
06 - Place shortcakes on prepared baking sheet. Bake 15-18 minutes until golden brown. Cool on wire rack.
07 - Toss sliced strawberries with sugar and lemon juice. Set aside for at least 15 minutes to macerate and release juices.
08 - Beat cold heavy cream, powdered sugar, and vanilla extract with electric mixer until soft peaks form.
09 - Slice each cooled shortcake horizontally. Spoon macerated strawberries over bottom half, top with whipped cream, and cover with top half. Add additional berries and cream if desired.