Makes 2 loaves.
1 tablespoon sugar or honey
2 1/2 cups warm water
275g active sourdough start
6 tablespoons softened butter
8 cups flour (+/- 1/2 a cup depending on how thick your start is!)
1 tablespoon salt
Add everything to the mixer at the same time. Knead for 8 minutes until smooth and the bowl is mostly clean.
Shape into a ball and place it in an oiled bowl. Rise until doubled, this took my dough about 4 hours. Shape into two loaves and place in parchment/oiled loaf tins. Let rise until puffy and domed on top, this took my dough 3 hours. Bake at 350 for 30-35 minutes. Remove from the loaf tin and brush the tops with butter. Cool before slicing.