Preheat oven to 425 degrees. Line a baking sheet with parchment paper or a silicone baking mat, set aside.
In a large mixing bowl, whisk together the flour, sugar, baking powder, and salt. Cut in the butter using a pastry blender.
In a small bowl whisk together the cream and egg. Pour into dry ingredients until large clumps form. There will still be pockets of flour. Turn onto a lightly floured surface and knead for a few seconds to pick up an loose crumbs. Using a rolling pin, roll into an even layer, 3/4-inch thick.
Using a 2 1/2-inch or 3-inch round cookie cutter, cut 8 discs and transfer to the baking sheet. Brush edges and tops with the lightly beaten egg white.
Place in the oven and bake for 14-16 minutes or until the tops are golden brown.
Meanwhile, toss sliced strawberries in a bowl with sugar. Set aside.
Remove biscuits from the oven and transfer to a wire rack to cool for at least 15 minutes.
Meanwhile, in the bowl of a stand mixer fitted with the whisk attachment or in a large mixing bowl with a hand mixer, beat the heavy cream, powdered sugar and vanilla until stiff.
To assemble, cut the cooled biscuits in half. Spoon strawberries on, then dollop whipped cream over top. Place the top of the biscuit on and serve immediately.