• In a large bowl of a stand mixer, measure and stir the starter, sugar, and water until combined.
• Then add the rest of the ingredients except the kosher salt.
• Mix together with the dough hook attachment on low speed for 1-2 minutes, until it is just coming together. You want it to be shaggy.
• Cover with a clean towel and let autolyze (dough rest) for 45 minutes.
• After autolyzing, add the salt to the bowl and either knead by hand or mixer for 4-5 minutes until the dough fully comes together. Scrape the sides of the bowl as needed with a spatula. When it is done the dough should have an elasticity to it.
• Next, move the dough to an oiled low sided container (I use a dash of olive oil and spread it around.
• Next, you will complete an envelope fold. Basically, take one side of your dough and pull/stretch it up and to the center of the dough. Do this on all four sides and then flip it over. Be careful not to “rip” the dough.
• After the first time doing the envelope fold let sit for 50 minutes then repeat the envelope fold.
• Do these two more times for a complete time of 200 minutes. (The last fold is done at 150 minutes and followed by a rest for 50 minutes.)
• After the final 50-minute rest, transfer your dough to a clean counter and shape into a smooth ball. (Do not flour counter.)
• Place dough ball in a lightly oiled bowl top side up then flip so that the dough is lightly coated with oil. Place in a bag and tie the end shut or cover well with plastic wrap.
• Let sit at room temperature for 1 hour then transfer to the fridge for the bulk ferment and proof for 10-12 hours.

Bake Day

• The next morning take the sourdough bun dough out of the fridge and transfer to a clean counter or work surface. Again, no flour.
• Here is where we size and shape the buns. I usually want about a 100-gram bun which is pretty good size. Divide the dough evenly to make 16 rolls. You can use a gram scale if you would like to get equal pieces. (If you prefer a smaller bun I would say go ahead with 80 grams of dough and you will get about 20 buns.)
• After you have finished sizing and dividing the buns it is now time to shape them. Starting with one dough ball shape into a ball by working the dough down and around the bun. Then with your piece of dough on the counter cup it with your hand and roll it in a circular motion, no more than 4 times. (You don’t want it to be too tight. Then you will have really tall buns.) Place on a large sheet pan/cookie sheet that is lightly greased.
• Continue this until you have shaped all the buns. Flatten slightly with your palm. (This is a great way to help them not be too tall.)
• Let rise 1 hour in a warm place. With 15 minutes left of the rise time preheat your oven to 400 degrees. Then crack the egg, add a little water, and beat together. Using a pastry brush, brush the egg mixture on the bun tops.
• Bake for 23-25 minutes in the preheated oven, until golden brown on top and bottom of the buns.
• Cool on a cooling rack and enjoy! Great fresh or you can freeze these buns for future use.