• Make the roll dough by combining sourdough starter and warm water in a large bowl or bowl of a stand mixer. Allow to dissolve then add melted butter, sugar, and one egg. Mix well.
• Mix flour, baking powder, and salt then add 1 cup of the mixture to the roll dough. Add ½ cup of flour at a time until the dough is firm and slightly sticky. Cover the dough with a damp tea or kitchen towel and allow to ferment in the refrigerator for about 8 hours (or overnight).
• Make filling by combining softened butter, brown sugar, cinnamon, and flour in a mixing bowl.
• After the dough has fermented, roll out on a well floured surface in the shape of a rectangle with dough at about ¼ inch thickness.
• Rub filling all over the surface of the dough using hands to make sure it covers the surface completely.
• Cut the dough into eight 1½ inch strips (see note for) using a pizza cutter.
• Roll using a flat, metal spatula or bench scraper then flip onto the spatula to move easily to a 12" cast iron skillet or 9x13 casserole dish.
• Cover and allow to rise until doubled (about 2 hours).
• Bake at 350℉ for about 15 minutes.
• Allow to cool completely then ice liberally with cream cheese frosting.

Cream Cheese Frosting

• Combine softened cream cheese, powdered sugar, and vanilla in a bowl and mix with a hand mixer until the frosting is smooth. Allow to sit in the refrigerator while the rolls cool for best results.