Mix Ingredients: In a stand mixer, combine all ingredients, adding the flour last. Adjust flour as needed based on the starter's hydration.
Knead the Dough: Knead until the dough is smooth and elastic, about 10 minutes. Perform the windowpane test for doneness.
Bulk Rise: Let the dough rise in a warm place for 10-12 hours.
Divide and Shape: Split the dough into two equal parts. Roll each piece into a rectangle, then roll up and place in greased or parchment-lined loaf pans.
Second Rise: Allow the loaves to rise at room temperature for 2-4 hours until doubled in size.
Bake: Preheat the oven to 375°F (190°C). Optionally, apply an egg wash for a golden crust. Bake for 45 minutes or until golden.
Cool: Let the loaves cool completely before slicing.