This is similar to the famous bread from Leidenheimer bakery in NOLA. They make theirs pretty squat, maybe 2 inches flat. Since it will be sliced and filled and pressed, that makes such things easier.
Place all the dry ingredients and butter into the mixing bowl of a stand mixer.
Start the machine on low speed, using the dough hook, and add the water to the bowl’s contents.
Mix on low speed for 4 minutes.
Mix on medium for an additional 4 minutes.
Remove the dough from the mixing bowl. Roll the dough on the counter to shape into a round, place in a buttered glass or metal bowl. Place the dough seem side up. Move the dough ball to coat with butter and turn the bough over, placing seam side down, and cover with plastic wrap. Allow to rest 30 minutes.
Lift dough from the bowl and gently pull the dough apart a few inches, bring the ends together. Turn the dough 45 degrees and repeat the pull and return process again. Repeat the turn and pull and return 2 more times, stretching and returning a total of 4 times. Shape the dough into a round and replace into the buttered bowl for an additional 30 minutes.
Gently turn the dough out onto a lightly floured counter. Shape the dough into a round, place on a prepared sheet pan (parchment paper or silicone baking sheet lined) and brush the loaf with milk then sprinkle with sesame seeds.
Allow the dough to stand 10 minutes to allow the milk to evaporate then lay plastic wrap on top until the loaf has doubled in size.
Place in the oven, reduce the temperature to 375° F and bake 25 minutes or until the loaf is baked.
Allow to cool completely before slicing.