In a large bowl, mix the sourdough starter, water (start with 1.5 cups), salt, and yeast.
Then, add 1 cup of flour. Stir until starting to mix. Then, add all the mix-ins + shredded parmesan. Stir together until well mixed.
Add the rest of the flour + mix (until there is no more dry flour remaining).
If the dough is too dry, add a bit of water - 1 Tbsp at a time. I usually need to use almost the full 2 cups of water (but I always start with 1.5 and go from there as needed). The dough should be soft and feel like an earlobe/baby’s bottom.
Then, turn the dough out onto a lightly floured surface. Have extra flour on standby as needed. Flour your hands and begin to knead. Start with a bench knife if the dough is too sticky to work with.
Add more flour as necessary until the dough is smooth and no longer sticky - meaning if you palm the dough, nothing clings to your palm. It should be a supple dough. Soft, not stiff. Again, like an earlobe/baby’s bottom. (Don’t clean your floured surface; you’re going to need it again.)
Oil the large bowl you used to mix your dough (using cooking spray or your preferred method), and let the dough rest in it for 60 minutes. Cover the bowl with plastic or place it in a plastic-proofing bag.