2½ Tsp baking powder
2 Tsp kosher salt
2 Tsp sugar
¼ Tsp baking soda
3½ cups all-purpose flour, plus more for surface
1 cup (2 sticks) chilled unsalted butter, cut into ½-inch pieces, plus more, melted, for brushing
1 cup chilled buttermilk
1. Preheat oven to 425°F. Mix baking powder, salt, sugar, baking soda, and 3½ cups flour in a food processor to combine. Add chilled butter and pulse until the largest pieces of butter are the size of a pea.
2. Transfer to a large bowl and gradually drizzle buttermilk over top, tossing with a fork as you go to incorporate. Knead the mixture a few times in bowl until a shaggy dough forms, it could look dry, then turn out onto a clean surface and pat into a 1 inch thick square.
3. Using a knife, cut dough into 4 pieces. Stack pieces on top of one another, sandwiching any loose dry bits of dough between layers, and press down to flatten. Lift up dough with a bench scraper, or any wide flat tool, and dust surface with flour.
4. Roll dough into a 1 inch thick rectangle and trim a thin border around sides of dough to create clean edges. Cut into a 4x3 grid to make 12 biscuits (don’t re-roll scraps). Transfer to a parchment-lined baking sheet, spacing 2 inches apart. Freeze for 10 minutes.
5. Brush tops of biscuits with melted butter and place in oven. Reduce oven temperature to 400°F and bake biscuits until deep golden brown on bottom and golden on top, 20–25 minutes.
6. Cool and serve!
Enjoy with Sandpiper's Loaded Clam Chowder