Buttermilk Biscuits with Burnt Onion Butter

• 2 tablespoons sugar
• 2 tablespoons baking powder
• 1 tablespoon kosher salt
• 2 teaspoons baking soda
• 4 cups all-purpose flour, plus more for surface
• ¾ cup (1½ sticks) unsalted butter, frozen 30 minutes
• 2 large egg yolks
• 1⅓ cups buttermilk

Burnt Onion Butter (click for recipe)

1. Heat oven to 375°. Whisk sugar, baking powder, salt, baking soda, and 4 cups flour in a large bowl. Using the large holes of a box grater, grate butter into dry ingredients, tossing to coat as you go.
2. Whisk egg yolks and buttermilk in a medium bowl. Using a fork, mix buttermilk mixture into dry ingredients, then gently knead a few times just until a shaggy dough comes together.
3. Transfer dough to a lightly floured surface and pat out until 1” thick; quarter dough and stack pieces on top of one another and press down to adhere (this will create flaky layers). Roll out dough until 1” thick. Using a 2”-diameter biscuit cutter, cut out biscuits, rerolling scraps as needed.
4. Place biscuits on a parchment-lined baking sheet. Bake until golden brown on the tops and bottoms, 20–25 minutes (a few minutes longer if baking frozen). Serve warm with Burnt Onion Butter.
5. Do Ahead: Dough can be made 1 month ahead. Freeze biscuits on a baking sheet, then transfer to resealable plastic bags. Keep frozen.