Roast sweet potato: Preheat oven to 400 F. Wash and scrub sweet potato and place it on a parchment or foil-lined baking sheet. Poke hole all over the surface of the sweet potato with a paring knife or fork.
226 grams sweet potato
Bake the sweet potato for 40 to 50 minutes or until the skin is puffy and flesh is soft. Take the sweet potato out of the oven and let it cool completely.
You can roast the sweet potato up to 2 days in advance. Store in an airtight container in the refrigerator.
Make the dough: Blend the sweet potato with the wet ingredients. Set aside.
169 grams sourdough discard, 75 grams buttermilk
Whisk the dry ingredients together in a large mixing bowl.
20 grams sugar, 210 grams all-purpose flour, 10 grams baking powder, ½ teaspoon baking soda, 6 grams salt
Toss the butter into the dry ingredients and work it in using your fingers or a pastry cutter.
113 grams unsalted butter
Make a well in the center of the flour mixture. Pour the wet ingredients in the center.
Using a wooden spoon or spatula, stir the ingredients together. Knead the dough 4 to 5 times until it comes together into a cohesive mass with only a few dry traces of flour.
Laminate the dough: Dust your work surface heavily and coat your hands with flour. (Use up all 30 grams).
30 grams all-purpose flour
Turn the dough out on to the heavily floured work surface. Using your hands, flatten the dough out into a rough rectangle about ¼-inch in thickness (size doesn't have to be exact).
Using a bench scraper, divide the dough into thirds that are roughly the same size. Stack the pieces together, adding any dried flour in between the layers of dough.
Shape the dough: Flatten the dough into a 5 by 8-inch rectangle, about ½-inch thick using floured hands or a rolling pin. Cut out 6 portions of dough.
Gently knead the dough until it comes together. Flatten it out into a 3 by 8-inch rectangle. Cut out 2 to 3 more portions of dough.
Place the dough rounds on a parchment-lined baking sheet. Move the baking sheet to the refrigerator.
Prep: Preheat oven to 400F.
Bake: Brush the top of the dough with buttermilk. Bake the dough for 20 to 25 minutes or until the biscuits have puffed up and the tops are golden brown.
Transfer the biscuits to a wire rack and let them cool for 5 minutes before serving.
Enjoy: These biscuits are best eaten the same day they are baked.
Store: Leftovers are best stored in an airtight container at room temperature for 2 days.