Sweet Potato Butter lightly adapted from: Toast and Jam
Make the Biscuits:
Preheat the oven to 450 F. In a large bowl, whisk together the flour, baking powder, salt and baking soda. Add the butter and toss to coat. Either using a pastry blender or your fingertips, work the butter into the dry ingredients (with your fingers, pinch the butter into the flour repeatedly until the mixture resembles large crumbs; it’s ok if some of the mixture is as large as small peas – it doesn’t all have to be uniform). Stir in the buttermilk and mix with a fork until the dough gathers together. If you need a little extra buttermilk, add it 1 tablespoon at a time.
Scrape the dough out onto a lightly floured work surface and pat it into a 1 1/2 inch-thick round. Using a 2 1/2-inch round biscuit or cookie cutter, cut into rounds (dip the cutter in flour in between to avoid sticking). If you’ve got biscuit scraps, repeat to try and use them up. Arrange biscuits in a 12-inch cast iron skillet as close together as possible. Sprinkle tops with sea salt. Bake for 14-16 minutes, or until golden brown. Serve warm.
Make the Sweet Potato Butter:
Place the sweet potato, apple, grapefruit juice and lemon juice in a food processor and process on high until the mixture is relatively smooth.
Transfer to a medium saucepan, stir in the remaining ingredients, and place the pan over medium heat. Cook down for about 20 minutes, stirring occasionally. The mixture will bubble and hiss quite a bit. Continue cooking until it thickens and smells caramelized. Stir often to avoid burning or sticking. Transfer the sweet potato butter back to the food processor and process until smooth and velvety. Spoon into clean jars and refrigerate for up to a month.