Buttermilk Biscuits

Chill the fats. Cut the ½ cup of butter into ½-inch pieces and refrigerate it along with the shortening so everything stays cold.

Mix the dough. In a food processor fitted with the steel blade, pulse together the cake flour, ¾ cup of the all-purpose flour, baking powder, baking soda, and 1 teaspoon of sea salt. Add the cold butter and shortening and pulse until small crumbles form, about 6 to 8 times. Add the buttermilk and pulse until a dough ball forms, about 5 to 6 times.

Shape it. Dust a work surface with flour and have the remaining 1 cup of all-purpose flour ready for kneading. Turn the dough out onto the floured surface. With floured hands, gently press the dough into an 11 × 8-inch rectangle about ¼ to ½-inch thick. Dust lightly with flour and fold it over in thirds, like a letter. Roll or press it back out to a 6 × 6-inch rectangle, about 2 inches thick.

Cut. With a pizza cutter, cut the dough into 9 squares (2 × 2 inches each).

Rest. Transfer the biscuits to a silicone mat or parchment-lined baking sheet about ½-inch apart. Cover loosely with plastic wrap and let them rest at room temperature for 15 minutes.

Preheat to 500°F during the rest.

Top. Brush the tops of the biscuits with the melted tablespoon of butter, then sprinkle with the remaining ¼ teaspoon of sea salt.

Bake. Place the baking sheet in the middle of the oven and immediately turn the oven down to 450°F. Bake for 12 to 16 minutes, until deeply golden brown.

Move the biscuits to a wire rack (or a cloth-lined basket — see notes) and let them cool for a few minutes before serving.