Place bread flour, yeast, 1 teaspoon salt, 1 teaspoon sugar, and caraway or celery seeds in food processor. Pulse to blend.
With machine running, gradually add hot water through feed tube, adding just enough to form a smooth dough. Process 1 minute to knead.
Place dough in a greased (with oil) bowl, turning to coat dough in oil. Cover loosely in plastic wrap and let rise in a warm, draft-free area until doubled in size, about 30 to 40 minutes.
Punch dough down and knead on a lightly floured surface until smooth. Divide dough into 12 pieces.
Form each piece of dough into a ball. Place dough balls on a baking sheet that has been lightly floured.
Flatten each ball slightly and use a serrated knife to cut an "X" on top of each one. Cover with a towel and let rise until doubled, about 20 minutes.
Preheat oven to 375 degrees. Grease a baking sheet and sprinkle with cornmeal.
Bring 8 cups of water to boil in a large saucepan. Add baking soda and 2 tablespoons sugar.
Add 4 rolls at a time, cooking 30 seconds per side. Transfer to prepared pan using a slotted spoon (X side up).
Brush rolls with egg white and sprinkle generously with salt.
Bake rolls until brown, about 25 minutes.