Old family recipe. Probably inaccurate and probably needs work, as I'm copying from old notes and memory.
Mix:
Let that sit for five minutes, then add:
The vegetable oil and sugar probably can be skipped; I expect the oil cuts down on gluten formation, and the sugar helps feed the yeast.
It may be helpful to put a container of boiling water under the sourdough container, or maybe keep it warm with a warming oven, if you have one of those. On the other hand, longer colder ferments are also a thing these days.
Feed the starter for a few days, maybe 1c flour and 3/4c water. Keep it covered.
Combine the following with each cup of sourdough.
Separate the egg whites into a different bowl, beat until soft peaks form. Fold egg whites into dough just before cooking.
There may also have been some vanilla added in some versions.