The best, soft sourdough sweet rolls with the addition of orange and cinnamon. These have orange zest in the dough, in the filling, and in the icing for maximum orange flavor. Make these for any special breakfast or brunch - they're especially perfect for Christmas and Easter brunches.
In a large skillet, melt the butter over medium-low heat. Once melted, remove from heat and pour in the milk. Set aside to cool while you mix the other ingredients. You want it to be what feels like good bath water temperature before adding to the dough.In a large bowl, combine the starter, sugar, and egg. Add in the warm milk mixture. Add flour, orange zest, and salt and mix until no dry spots remain. Scrape down the sides of the bowl, cover, and rest for 30 minutes. Turn dough out onto a lightly floured surface. Knead for 3-4 minutes, until a smooth dough forms. Place in a large buttered bowl, cover, and let rise at room temperature until doubled in size - about 8-12 hours.
For the Filling
Mash the brown sugar, zest, and cinnamon together in a medium bowl until fragrant. Stir in the melted butter - it should be the texture of wet sand.
Shaping the Rolls + Second Rise
Butter a 9-inch round pan OR line it with parchment paper that's been balled up and unballed a couple times. Turn dough out onto a generously floured surface. Press it into a flat disc and shape into a rough rectangle with your hands. Roll it into a 12 by 20-inch rectangle, adding more flour as needed so it doesn't stick to the rolling pin or the work surface. Sprinkle the sugar filling over the dough, spreading evenly with your hands. Leave a 1-inch strip at one of the longer ends uncovered by filling. Starting at the opposite long end, begin rolling the dough tightly into a log. Pinch to seal.Use a bench scraper, knife, or unscented dental floss to cut into (8 or 9) 2-inch rolls. Place them in the prepared pan. Cover and let rest at room temperature for 1-4 hours, until significantly puffed up.
Baking the Rolls
When the rolls are nearing the end of their second rise, preheat the oven to 350 degrees.Bake on the middle rack for 30-40 minutes, until cooked to your liking. If you like gooey rolls, check closer to the 30-minute mark. Let the baked rolls cool for 10-15 minutes before icing.
For the Icing
Whip the cream cheese and butter together in a stand mixer fitted with the whisk attachment or with a hand mixer until light and fluffy - about 2 minutes on high speed, scraping down the sides of the bowl as needed. Add the powdered sugar, orange zest and juice, and vanilla and continue mixing for a 1-2 minutes until well combined and fluffy. Add more powdered sugar or a splash of milk as needed to get the consistency you want.Ice the rolls and enjoy warm.