I confess the idea of using a starter for these was tempting. I found a few notes here and there on some recipe boards to the effect that a starter would be “traditional” for bialys. I’m inclined to dispute that. Bialys were invented in Bialystok, Poland around the year 1880. Which means they are by any definition a “modern”, “city” bread, made with the packaged brewer’s yeast that would have been commonly available at the time. Considering how much the Poles have always loved light, fluffy, fast-rising breads I think the odds of bialys being sponge-raised are remote. Still I’m not stickler for authenticity. Some of dough or starter would work well here. Substitute either for up to 1/3 of the dough, making sure the 50% hydration ratio is retained, and making sure you use high gluten or bread flour for either preferment.
2 cups (10 ounces) high-gluten or bread flour
1/2 teaspoon instant yeast
1 teaspoon salt
5 ounces (2/3 cup minus a teaspoon) water at room temperature
1/2 recipe caramelized onions, chopped
In the bowl of a mixer fitted with the paddle, stir together the flour, instant yeast and salt. Add the water in a steady stream, stirring until the flour is moistened. Switch to the dough hook and knead the dough about 7 minutes. Remove the dough to a lightly oiled bowl and let it rise about 1 1/2 hours until doubled.
At that point remove the dough to a floured board and deflate it. Divide it into 5 pieces and shape the pieces into balls by gathering the cut edges edges together and pinching them closed. Place them smooth-side-up on a tray lined with a floured cloth. Sprinkle them amply with flour and cover with another towel or plastic wrap for another 2 hours.
About an hour into the proofing, preheat your oven to 500 degrees Fahrenheit, making it as brick-oven like as you can beforehand.
To shape, pick up a piece of dough and, with both hands, start rotating the dough ball, pinching it in the center to flatten it the middle, leaving a cornice around the lip. Put the circles on a sheet of parchment paper. Using scissors or a knife, cut a small slit in the bottom to defeat any large bubbles that might want to rise while the bialys are baking. Spoon about 2 tablespoons of caramelized onions into the centers and let the bialys rest for 10-15 minutes to relax the gluten.
Slide the parchment sheet with the bialys onto the back of a sheet pan or cookie sheet. Open the oven door and, holding the sheet pan (but not the parchment) by the wide side, reach into the hot oven and plant the far edge of the pan on the far edge of the baking stone, then in one quick motion slip the pan out, leaving the parchment sheet with the bialys resting directly on the stone as shown here. Carefully pour about a up of water onto the empty sheet pan and spritz the sides of the oven, then close the oven door.
Bake the bialys about 8 minutes until they’re golden with some darker brown spots. Remove them from the oven with tongs and place them on a rack to cool. Eat them warm!