Daniel Ray, I use sourdough starter not supermarket yeast. I also use water kefir [not milk kefir] and what I do is substitute the water for the Kefir, in buildng the dough. I also don't knead the bread I do stretch and folds instead and long fermentations which makes a real flavourful bread.
If you are using supermarket yeast, and milk kefir I would suggest you proof your yeast to see if it's any good. Add to that 1 cup flour 1 cup of milk kefir and let it sit at room temperature [in the warmest art of your kitchen] covered over night then proceed to make up your dough. After making up the dough, let it rest for 1 hour. Come back and do stretch and folds. [ look at you bread in the 4 directions pick up the north and stretch up and over on itself, do the same for the east south and west. Let it rest again for about 30 minutes and do it again. Do this for about 4 more times. By doing this Nature is building up the gluten you need. AFter you're done, you can either let it rise until double and proceed to bake your bread or what I do is cover it with cling film and then put it in a kitchem size garbage bag and put it in the fridge over night. Take it out and form it and bake it off as usual.
