Place the flour, sourdough starter, milk, sugar, butter, yeast (if using), and egg in the bowl of a stand mixer. Use a paddle attachment to mix the ingredients on low speed until a sticky dough forms. Sprinkle the salt in an even layer over the dough, cover, and allow the dough to rest for about 20 minutes.
After the dough rests, using the mixer fitted with a paddle attachment, mix the salt into the dough on low speed for about 1 minute then increase the speed to medium. Continue to beat for an additional 2 to 3 minutes. The dough should have a smooth texture. Leave the dough in the bowl, but remove the bowl from the mixer. Cover and let rest for 4 hours while completing 1 set of stretch and folds every hour. While the dough is resting, prepare the filling.
1 teaspoon salt
Filling:
In a small bowl, combine the butter, brown sugar, and cinnamon. The mixture will have the texture of thick, wet sand. Set aside.
3 tablespoons (42 g) unsalted butter, 1 ½ tablespoons ground cinnamon, ½ cup (107 g) light brown sugar
After the dough rests for 4 hours, transfer it to a lightly floured surface. Roll the dough out into a rectangle roughly 14 x 16 inches. Spread or crumble the cinnamon sugar filling over the rectangle of dough. Start with the longer side of the rectangle and roll the dough into a tight log with the filling in the center. The dough will lengthen about 4 inches as you roll.
Use a bench scraper or sharp knife to trim the ends if desired then cut the dough into 8 to 10 equal-sized pieces (about 1 ½ to 2 inches thick). Lightly grease a 9 x 13-inch baking dish with butter or cooking spray, then transfer the rolls to the pan. Cover with plastic wrap or a clean towel. Allow the rolls to rise in a warm area for 2 to 3 hours before baking. They will appear puffy in appearance and may fill out the space in the pan. However, they may not necessarily double in size.
Preheat the oven to 350°F, and bake the cinnamon rolls in the preheated oven for 25 to 30 minutes or until the tops are golden brown. While the cinnamon rolls bake, make the glaze.
Glaze:
In a small bowl, combine the powdered sugar, milk, and vanilla. Start with less milk and add additional to reach the desired consistency. Set aside.
1 ½ cups (170 g) powdered sugar, 4 to 5 tablespoons (70 g) whole milk, 1 teaspoon pure vanilla extract
Remove the cinnamon rolls from the oven and allow to cool until they’re just barely warm to the touch before adding the glaze.
Drizzle the glaze over the cinnamon rolls, and serve warm. Store leftovers in an airtight container at room temperature for up to 3 days or in the refrigerator for up to 4 days.
Notes
*The calories listed are an approximation based on the ingredients in the recipe card and a serving size of 1 sourdough cinnamon roll. Actual calories will vary.*For more information and tips, please refer to the post.