Bialys are like bagels, but they're baked instead of boiled. Lots of chopped onion and poppy seeds are a tasty topping.
Whisk together lukewarm water, yeast and sugar in a large bowl until the yeast dissolves. Stir in 1 cup flour. Stir in salt and enough additional flour to make a soft dough, about 2 1/2 cups.
Turn the dough out onto a lightly floured surface and knead, gradually incorporating more flour as needed to prevent sticking, until the dough is smooth and elastic, 8 to 10 minutes. Cover the dough with a clean dish towel and let rise for 45 minutes.
Meanwhile, line 2 baking sheets with parchment paper, lightly sprinkle with cornmeal and set aside.
Stir together onion, poppy seeds and oil in a small bowl and set aside. Whisk the egg and 2 tablespoons water together in another small bowl.
When the dough has risen, punch it down and divide it into 12 equal pieces; cover and let rest for 10 minutes. Roll or stretch each piece into a 4- to 5-inch oval and place on the prepared baking sheets.
Brush each bialy with the egg-and-water mixture and sprinkle with a heaping tablespoon of the onion-poppy-seed mixture and some salt. Cover with a floured dish towel and let rise until they appear puffy, 30 to 40 minutes.
Preheat oven to 450 degrees F. Place the bialys in the oven, reduce the heat to 425 degrees F and bake until golden brown, 20 to 25 minutes.
2 1/2 starch