Step 1

Preheat the oven to 425ºF and set an oven rack in the middle position. Line a 13x18-inch baking sheet with parchment paper.

Step 2

In a large bowl, whisk together the flour, cornstarch, baking powder, baking soda, sugar, and salt. Add the butter and, using a pastry cutter, cut the butter into the dry ingredients until the mixture resembles coarse sand with a few pea-sized clumps of butter intact. (Alternatively, you can use your fingertips to rub the butter into the mixture.) Add ¾ cup of the buttermilk and stir with a rubber spatula until the dough comes together into a shaggy, sticky mass. Add the remaining ¼ cup buttermilk, a little at a time, until the dough is moistened (you may not need all of it). Do not over-mix.

Step 3

Using two soup spoons, scoop 8 peach-size mounds (about 2½ inches) of the biscuit dough onto the prepared baking sheets, spacing them evenly apart. Do not compact the mounds or try to make them smooth on top; they are meant to have an irregular shape. Bake for 17 to 20 minutes, until the biscuits are lightly golden. Brush the biscuits with melted butter, if you like. The biscuits are best served warm out of the oven (though a few minutes in the oven will revive slightly older biscuits). Once cool, freeze any biscuits you don't plan to serve right away.

Step 4

Freezer-Friendly Instructions: The biscuits can be frozen, unbaked, for up to 3 months. Bake without thawing, but allow a few extra minutes in the oven.