In the bowl of your stand mixer add the water, oil, honey, starter, egg (if using), and the oats. Mix well.
Add 3 cups of flour and mix in.
Add salt.
Continue adding flour just until the dough starts to pull from the sides of the bowl.
Allow to knead for 10 minutes. The dough will start out sticky but will come together after kneading and developing the gluten.
Turn onto a work surface and shape into a loaf shape.
Put in greased loaf pan, cover, and allow to rise for 4-8 hours.
Once dough rises to the top of the pan, preheat the oven to 350 degrees F.
Bake for 35-40 minutes or until internal temperature reaches 190-200 degrees F.
Promptly remove loaf and put on cooling rack to cool completely before slicing.