Prepare the strawberries: Quarter the strawberries and mix with 1/4 cup sugar in a large bowl. Cover and refrigerate for at least 15 minutes to allow juices to develop.

Make the biscuit dough: Preheat oven to 400°F (204°C). In a large bowl, whisk together flour, sugar, baking powder, baking soda, and salt.

Cut in butter: Add cold cubed butter to dry ingredients. Use a pastry cutter or food processor to cut butter into flour mixture until coarse crumbs form.

Add buttermilk: Pour cold buttermilk over mixture and gently fold with a spatula until dough just comes together. Don't overmix - dough will be shaggy.

Shape the dough: Turn dough onto floured surface. With floured hands, flatten to 3/4 inch thick. Fold both ends toward center, turn, and flatten again. Repeat folding process two more times for flaky layers.

Cut biscuits: Using a biscuit cutter, cut straight down without twisting. Place biscuits touching each other on a baking sheet or in a cast iron skillet.

Bake biscuits: Brush tops with heavy cream and sprinkle with coarse sugar. Bake for 18-22 minutes until golden brown. Cool for 10 minutes.

Make whipped cream: In a mixing bowl, beat cold heavy cream, 2 tablespoons sugar, and vanilla with electric mixer on medium-high speed until soft peaks form, about 3 minutes.

Assemble shortcakes: Cut each biscuit in half horizontally. Place bottom half on plate, spoon strawberries with juices over it, add dollop of whipped cream, and top with other biscuit half. Serve immediately.