Macerate the Strawberries: In a large bowl, combine the quartered strawberries with 1/4 cup of sugar. Stir well to coat the berries evenly. Cover the bowl and refrigerate for at least 30 minutes to let the strawberries release their natural juices and develop a syrupy texture.
Prepare the Biscuit Dough: Preheat your oven to 400°F (204°C). In a large mixing bowl—or a food processor—whisk together the flour, sugar, baking powder, baking soda, and salt until evenly combined. Add the cold cubed butter and use a pastry cutter (or pulse in the processor) to cut the butter into the flour until the mixture resembles coarse crumbs.
Add the Buttermilk and Bring Dough Together: Pour the cold buttermilk over the crumbly flour mixture. Gently fold the dough together using a silicone spatula or wooden spoon. The dough should be shaggy and slightly sticky with visible lumps of butter. Avoid overmixing.
Laminate and Shape the Dough: Turn the dough onto a well-floured surface. With floured hands or a floured rolling pin, flatten it into a 3/4-inch thick rectangle. Fold one short end toward the center, then fold the other end over like a letter. Rotate the dough and repeat the folding and flattening process two more times. This creates flakier layers in the biscuits.
Cut and Arrange the Biscuits: Roll the dough out one last time to about 3/4 inch thick. Using a 2.75- or 3-inch biscuit cutter, cut out as many rounds as possible. Press straight down—don’t twist—to keep the biscuits rising evenly. Reroll and cut any remaining dough scraps. You should end up with 10–12 biscuits.
Bake to Golden Perfection: Place the biscuits close together in a greased 10-inch cast iron skillet or on a parchment-lined baking sheet. Brush the tops with 2 tablespoons of heavy cream or buttermilk, then sprinkle with coarse sugar. Bake for 18–22 minutes or until the tops are golden brown. Remove from oven and let cool for at least 10 minutes before assembling.
Whip the Cream: In a separate bowl, beat the heavy cream, remaining 2 tablespoons sugar, and vanilla using a hand or stand mixer fitted with a whisk. Whip on medium-high speed for about 3 minutes or until soft to medium peaks form. Keep chilled until ready to use.
Assemble the Shortcakes: Slice each biscuit horizontally. Layer the bottom half with spoonfuls of juicy strawberries and a generous dollop of whipped cream. Cap with the biscuit top and add more whipped cream and berries if desired. Serve immediately for best texture and flavor.