Mix flour, water, and starter. Make sure that all flour is hydrated. Let the dough rest for at least an hour.

Add salt and perform one set of stretch and fold.

Let the dough ferment for 3- 4 hours, or until it has doubled in size at a temperature of 78ºF/25ºC. Use the dough-in-the-glass test described above. You can perform 3-4 stretch and fold sessions during the bulk fermentation.

Lightly flour your work surface and dump out the dough. Divide it into ten pieces with your bench knife. Form each piece of dough to a roll.

Let the rolls rise for at least an hour. Preheat the oven to 480ºF / 250ºC together with a baking stone if you have one. Otherwise, you can use a baking sheet.

Chop the onion and mince the garlic. Sautee the onion on medium heat for 2-3 minutes in olive oil or butter. Add garlic at the end. Add salt to taste.

Dust your working surface with flour and start forming the bialys. Make an indent in the middle of the roll and work outwards until a 1-inch rim remains. Make sure to get the bottom as thin as possible.

Transfer the bialy to a parchment paper and fill the indent with onion and garlic and sprinkle some rosemary on top.

Bake for 20-30 minutes or until the bialys has got a nice golden brown color.