Place a medium bowl (preferably metal) in the freezer to chill. (If space is limited, place in the refrigerator.)
Preheat oven to 400°F. Line a baking sheet pan with parchment paper.
Wash, dry, zest, and juice limes into a medium saucepan.
2 limes
Add sugar and water to the saucepan; place over medium-low heat and cook, stirring occasionally, until sugar dissolves. Bring to a boil, then remove from heat.
½ cup granulated sugar
2 fl oz (¼ cup) water
Wash and dry blackberries. Add to the saucepan with the sugar syrup, stir to coat, and set aside to cool.
2 (6 oz) pkgs blackberries
Meanwhile, place flour, sugar, baking powder, and salt in another medium bowl; whisk to combine.
1 cup all-purpose flour
1 tbsp granulated sugar
1 ½ tsp baking powder
⅛ tsp salt
Using a box grater, coarsely grate cold butter into the bowl with the flour. Using two hands, combine the flour and butter by rubbing the mixture between your thumbs and fingers until it looks crumbly. Add cream and stir until the dough comes together.
¼ cup butter, unsalted
4 fl oz (½ cup) heavy cream
Divide the dough into 4 equal-sized pieces and pat each into a disk, 3-inches in diameter by ¾-inch tall; place on the baking sheet, spacing 2-inches apart.
Remove bowl from the freezer. Measure cold cream into the bowl. Brush tops of the shortcakes with a small amount of the cream (reserving the rest for the whipped cream) and sprinkle with sugar.
8 fl oz (1 cup) heavy cream
1 tsp granulated sugar
Place shortcakes in the oven and bake until lightly golden around the edges, about 18 minutes. Remove from oven and let cool.
Meanwhile, add sugar and vanilla to the bowl with the cream; use a whisk (or hand blender) to beat the cream vigorously, until medium-soft peaks form, about 3 minutes if whisking. (When you pull the whisk out of the bowl, the cream should hold its shape, with a peak that curls over slightly.)
2 tsp granulated sugar
½ tsp vanilla extract
Place whipped cream in the refrigerator while the shortcakes finish baking.
To serve, divide blackberries with lime syrup, shortcakes, and whipped cream between bowls. Enjoy!