01 - Preheat oven to 425°F. Line a baking sheet with parchment paper.
02 - In a large bowl, whisk flour, sugar, baking powder, and salt until combined.
03 - Cut in cold butter with a pastry cutter or fingers until mixture resembles coarse crumbs.
04 - In a separate bowl, whisk milk, egg, and vanilla until blended.
05 - Pour wet ingredients into dry ingredients and stir until just combined. Do not overmix.
06 - Drop dough by large spoonfuls onto the prepared baking sheet to make 6 mounds. Bake for 15 to 18 minutes until golden brown. Cool completely.
07 - Combine strawberries, sugar, and lemon juice in a bowl. Let sit for at least 15 minutes to release juices.
08 - In a cold mixing bowl, whip heavy cream, powdered sugar, and vanilla with an electric mixer until soft peaks form.
09 - Crumble or split cooled shortcakes. Layer pieces in the bottom of 6 clear cups. Add a scoop of strawberries with juice, then a dollop of whipped cream. Repeat layers as desired, finishing with whipped cream and a strawberry slice on top. Serve immediately.