Preheat oven to 425 degrees. Line a large baking sheet with parchment paper or silicone baking mats.
Whisk together flour, cornstarch, 1/2 cup sugar, baking powder, baking soda, and salt. Using pastry cutter, two knives, or a food processor, cut in butter about 1 teaspoon at a time.
Using a food processor fitted with dough attachment, or a large spoon, mix in whipping cream and vanilla extract until a ball of dough is formed.
Lightly flour a working surface. Roll dough out on surface to be about 3/4" thick. Use a 2 1/2" biscuit cutter to cut biscuits. Place biscuits on prepared baking sheet, leaving biscuits about 2 inches apart. Sprinkle tops of biscuits lightly with sugar. Bake for 12-13 minutes, or until tops are golden brown.