Preheat the oven to 400°F. Line a baking sheet with parchment paper.
In a large bowl, whisk together the flour, sugar, baking powder, and salt.
Using a pastry cutter or your fingers, cut in the butter until the mixture resembles coarse crumbs.
In a small bowl, whisk together the heavy cream, egg, and vanilla extract.
Add the wet ingredients to the dry ingredients and stir until just combined.
Turn the dough out onto a lightly floured surface and knead gently until it comes together.
Pat the dough into a 1-inch thick circle and cut out 6 rounds using a biscuit cutter.
Place the rounds onto the prepared baking sheet and bake for 15-18 minutes, or until golden brown.
While the shortcakes are baking, prepare the strawberries. In a medium bowl, toss the sliced strawberries with the granulated sugar and set aside.
In a large bowl, beat the heavy cream until soft peaks form.
Add the powdered sugar, lemon zest, and vanilla extract and beat until stiff peaks form.
To assemble the shortcakes, split each one in half and place the bottom half on a plate.
Spoon some of the strawberries and their juices over the bottom half.
Top with a dollop of the lemon whipped cream.
Place the top half of the shortcake on top and repeat with the remaining shortcakes.
Serve immediately and enjoy!