1 package active dry yeast
3 tablespoons light brown sugar
5 tablespoons sorghum syrup, plus more for finishing
1 stick plus 2 ½ tablespoons unsalted butter, softened, plus more for greasing pan
2 eggs plus one yolk, at room temperature
1 cup cooked and mashed sweet potato
1 ¼ teaspoons kosher salt
2 cups all-purpose flour, plus more for surface
1 cup Red Fife bread flour or other whole-wheat flour
Flaky sea salt, for finishing

1. Use an electric mixer with paddle attachment to combine yeast, sugar, sorghum and milk, processing until sugar dissolves. Add 1 stick softened butter, two eggs and sweet potato, mixing until incorporated. Add kosher salt and mix again briefly. (Mixture may appear speckled.)
2. In a medium bowl, combine both flours. Switch mixer to dough hook attachment. Add flour in three batches to yeast mixture, mixing each addition until just combined. Once flour is incorporated, mix dough at medium speed until it starts to pull away from bowl.
3. Transfer dough to a large bowl greased with butter, cover with plastic wrap and set aside in a warm place. Allow dough to rise until it is doubled in size, 1-2 hours. (Alternatively, bring a large pot of water to a simmer, place bowl on stove next to simmering water and let rise.)
4. Return risen dough to mixer and knead using dough hook until smooth and elastic, 5 minutes. (Alternatively, knead dough by hand for 10-12 minutes.) Generously dust workspace with flour. Use a rolling pin to roll out dough to 1/4-inch thickness.
5. Use a 2 ½-inch biscuit cutter (or a glass cup) to cut out 24 rounds. (If you don’t quite get 24 rounds, you can re-roll dough scraps and cut-out the rest.)
6. Melt 2 tablespoons butter, then use a pastry brush to brush each dough round with melted butter. Use remaining butter to grease a 10-inch cast icon pan or two 6- to 8-inch pans.
7. Fold each dough round in half. Place folded dough halves around edge of pan. Cover with plastic wrap and let dough rise in a warm place until when you touch the dough lightly with your fingertip, the indentation remains, 20-25 minutes.
8. Preheat oven to 375 degree. Beat egg yolk in a small bowl, then brush rolls with egg wash. Bake rolls until golden, about 20 minutes.
9. Remove rolls from oven. Drop remaining ½ teaspoon butter in center of rolls, then drizzle sorghum over top. Sprinkle with finishing salt and serve.