Preheat oven to 400 degrees. Lightly spray 4 six inch sub molds with cooking spray or line a baking sheet with parchment paper
Sift dry ingredients into a large mixing bowl until there are no lumps. Add remaining ingredients and stir until a smooth dough has formed. If dough seems to not come together smoothly add small amounts of warm water until a smooth dough has formed
Form dough into a smooth ball and massage the dough in hands for 1 minute to be sure of texture. if dough is crumbly add small amounts of warm water until dough holds together and is smooth. Form dough back into ball and allow to sit for 5 minutes to absorb any extra moisture and allow ingredients to settle together
Line a clean worksurface with parchment paper. Divide dough into 4 equal portions. Form each dough portion into desired size and shape of hot dog bun. I usually form mine into a 6 inch log. Place each formed portion into prepared molds or lined baking sheet.
Make sure dough stays smooth at all times. For brown top stir together 1 TBS water with 1 large egg until fully combined. Brush egg wash lightly over tops of buns. Bake at 400 degrees for 15 to 20 minutes
Remove from oven. Cool in the molds or on the pan at least 15 minutes to firm up. Remove from molds and transfer to a wire rack. Allow to cool completely before slicing
When ready tp use slice in half vertically keeping one side of the bun attached. Use immediately or store leftovers in airtight container at room temperature up to 3 days