Instructions

Start the dough the night before

1. In a stand mixer or a large bowl, mix the flour, salt, coconut sugar, starter, and water into a thick sticky dough. In a stand mixer, use a dough hook and knead the dough gently for 2 minutes. Stop the mixer and let the dough rest for 5 minutes. Do this for 4-6 rounds, just until the dough is well developed. If mixing by hand, stir the ingredients together with a dough whisk until incorporated. Let the dough rest for several minutes. With lightly wet hands, stretch and fold the dough 4-5 turns every 5 minutes for 4-6 rounds until it's smooth and stretchy. It should be fairly sticky. Cover the dough and let the dough proof overnight at room temperature (65-70℉).

The next morning

1. Deflate the dough by doing a round of stretch and fold in the bowl. Let the dough rest for 5 minutes.
2. Turn the dough out onto a floured surface.
3. Gently roll and pat the dough into a log. Cut the dough into 6 or 8 equal portions. Working with one piece at a time, form nice tight balls of dough. Start by folding the top down to the center. Working clockwise with your right hand fold all the sides into the center and push them down firmly while turning the dough counterclockwise with your left hand.
4. After 8 or so turns the dough should feel tight and rounded. Pinch the bottom of the bun and roll it gently in your hands to further shape it. Place the buns on a sheet of parchment paper atop a baking sheet to help you transfer the buns to a preheated baking stone once proofed.
5. If baking on a baking sheet, proof the buns on parchment on the baking sheet — no need to preheat the baking sheet, in fact it might be wise to double the baking sheet to protect the bottoms from getting too dark.
6. Once all the buns have been shaped, cover them and let them proof again for 3-6 hours (the proofing time will totally depend on the climate, activity of the starter, and so many other factors). You want the dough to rise to at least double if not triple its original size.
7. Preheat your oven to 375°. If using a baking stone preheat the oven with the baking stone inside.
8. Mix the egg yolk and milk together in a small bowl. Using a pastry brush, lightly coat the top of each bun with egg wash. Sprinkle the buns with sesame seeds.
9. Slide the parchment with buns atop onto the preheated baking stone. Bake the buns for 30 minutes. Remove them from the oven and from the parchment paper to a wire rack to cool. Let them cool completely, before pulling them apart if they are touching.
10. Slice and top the soft and chewy buns with all your favorites! Enjoy your well-deserved burger!