Mix Ingredients: In a large bowl, combine the sourdough starter and warm water. Stir in the sugar, salt, and melted butter. Add flour gradually until a dough forms.
Knead Dough: Turn the dough onto a floured surface and knead for about 8-10 minutes until smooth and elastic.
First Rise: Place the dough in a greased bowl, cover with a cloth, and let it rise in a warm place for 4-8 hours or until doubled in size.
Shape and Second Rise: Punch down the dough, shape it into a loaf, and place it in a greased loaf pan. Cover and let rise for another 1-2 hours.
Preheat Oven: Preheat your oven to 375°F (190°C).
Bake: Bake for 30-35 minutes or until the bread is golden brown and sounds hollow when tapped.
Cool: Remove from the pan and let cool on a wire rack before slicing.