Preheat your oven to 400°F (200°C). Poke holes in a large sweet potato using a fork and place it on a baking sheet. Roast for 45-60 minutes, or until it's fork-tender and soft. Let it cool slightly, then mash it until smooth, measuring out ¾ cup for your sweet potato biscuits.

Lower the oven temperature to 425°F (220°C). In a large mixing bowl, whisk together all-purpose flour, baking powder, and table salt. Cut in ½ cup of chilled unsalted butter using a pastry cutter or your fingertips until the mixture resembles coarse crumbs, similar to pea-sized granules.

Add the previously mashed sweet potato and ½ cup of milk to the flour mixture. Gently stir until the dough comes together; it should appear shaggy but not overly wet. Take care not to overmix.

Lightly flour a clean work surface and turn the dough out onto it. Gently press the dough into a ½ inch thick slab, and fold the dough over itself 4-5 times to create layers. Use a biscuit cutter or a knife to cut out your biscuits.

Place the cut biscuits on the prepared baking sheet, making sure they are close but not touching. Bake for 12-15 minutes, or until the tops are beautifully golden brown and the biscuits have risen.