01 - Preheat the oven to 400°F. Line a large baking sheet with parchment paper.
02 - In a large mixing bowl, whisk together all-purpose flour, baking soda, salt, and granulated sugar.
03 - Add cold, cubed butter to the flour mixture and rub in using a pastry cutter or fingertips until the mixture resembles coarse crumbs.
04 - Pour in chilled buttermilk and gently stir with a fork until the dough just comes together.
05 - Turn the dough onto a lightly floured surface and knead briefly for about 30 seconds to create a soft, cohesive dough.
06 - Roll the dough into a rectangle about 1/2 inch thick. Cut into 10 equal strips, each approximately 1 inch wide.
07 - Twist each strip several times and arrange them on the prepared baking sheet, spacing apart.
08 - Brush each twist with beaten egg. Sprinkle with sesame seeds, poppy seeds, or grated Parmesan if desired.
09 - Bake for 20 to 22 minutes, until golden brown and flaky.
10 - Cool slightly on a wire rack. Serve warm or at room temperature.