Step 1

Place a rack in the center of the oven and preheat to 425 degrees F. Grease a cast iron skillet with butter.

Step 2

In a small bowl, whisk together the sweet potato and 1/3 cup buttermilk. Set aside.

Step 3

In a large bowl, whisk together the flour, sugar, baking powder, baking soda and salt. Cut in the butter with a pastry cutter or fork until the mixture resembles coarse meal. Add the sweet potato mixture and fold gently to combine. Add the remaining buttermilk a little at a time until all the flour is moistened. How much buttermilk you will need depends on the amount of moisture in your sweet potato.

Step 4

Sprinkle a small handful of flour on a work surface. Turn the dough out onto the surface and add honey and thyme leaves right into dough. Knead lightly 2 to 3 times with the palm of your hand until the mixture comes together. It's fine if some of the honey or thyme leaks out, just push back into dough. Pat the dough out into a 3/4 inch thick round.

Step 5

Using a biscuit cutter or the rim of a glass, cut the dough into biscuits.

Step 6

Gently re roll the scraps and cut out more biscuits until all dough is used. You should get 8 thick biscuits. Place the biscuits into the prepared skillet and bake until light golden brown and firm to the touch, 14 to 17 minutes. Serve these fluffy biscuits warm or at room temperature with a drizzle of honey.