Mix Fresh Strawberry (6 pint) with Lilac Sugar (4 tablespoon) in medium bowl; set aside while preparing shortcakes or up to 2 hours.
Adjust oven rack to lower middle position; heat oven to 400 degrees F (200 degrees C). Mix All-Purpose Flour (2 cup), Fine Salt (1/2 teaspoon), Baking Powder (1 tablespoon) and Lilac Sugar (3 tablespoon) in medium bowl.
Using large holes of box grater, grate Unsalted Butter (1/2 cup) into the dry ingredients. Toss butter with flour to coat. Use pastry cutter or a fork, to finish cutting butter into the flour. Or scoop up coated butter with both hands, then quickly rub butter into dry ingredients with fingertips until most of butter pieces are the size of split peas.
Mix Egg (1) with Greek Yogurt (1/4 cup) and Milk (1/4 cup); pour into flour mixture. Toss with fork until large clumps form. Turn mixture onto floured work surface and lightly knead until it comes together.
Pat dough into 9- by 6-inch rectangle, 3/4 inch thick. Flour a 2 3/4-inch biscuit cutter; cut 6 dough rounds. Place rounds 1 inch apart on small baking sheet lined with parchment; brush dough tops with Heavy Cream (1 tablespoon) and sprinkle with remaining Lilac Sugar (2 tablespoon).
Bake until golden brown, 12 to 14 minutes. Place baking sheet on wire rack; cool cakes until warm, about 10 minutes.
Chill a non-reactive, deep bowl and beaters mixer in freezer for at least 20 minutes.
Add Heavy Cream (3/4 cup) and Lilac Sugar (1 tablespoon) to the chilled bowl; beat on low speed until small bubbles form, about 30 seconds. Increase speed to medium; continue beating until beaters leave a trail, about 30 seconds more. Increase speed to high; continue beating until cream is smooth, thick, and nearly doubled in volume, about 20 seconds for soft peaks.
Add in the Greek Yogurt (1/4 cup) and whip for another ten seconds or so, until whipped cream is thick. If necessary, finish beating by hand to adjust consistency.
Split each cake crosswise by hand; spoon a portion of berries and then a dollop of whipped cream over each cake bottom. Cap with cake top; serve immediately and enjoy!