Combine the warm water, brown sugar & yeast in a bowl until dissolved and set aside until foamy.
Add the bread flour, cornmeal, buttermilk, oil, mustard, salt, and yeast mixture to a mixer bowl fitted with a dough hook.
Mix on low to combine and scrape the bowl if needed.
Continue mixing on low until a smooth, stiff dough forms, about 10 minutes.
Cover and rise until doubled, 1-2 hours.
Portion dough into 10 balls, about 90 grams each and rest covered 10 minutes before rolling.
Roll on an un-floured surface into a 22” rope, twist, then flip seam side down.
Place on a parchment lined tray and freeze until firm, about 2 hours or up to overnight.
Preheat the oven to 450F.
Combine the poaching ingredients in a wide pot and bring to a simmer.
Poach the frozen pretzels, a few at a time, bottom side up, and simmer for 30 seconds.
Remove to a clean towel to drain, then place on greased parchment, side by side & brush with egg white and sprinkle with salt.
Bake until deep golden, about 10-13 mins.
