What is a Hokkaido milk bun, and why does it make a better burger?
Quick answer: A Hokkaido milk bun is a Japanese style of enriched milk bread made using tangzhong, a cooked paste of flour and liquid that is mixed into the dough. The technique lets the dough hold significantly more moisture, producing bread that is unusually soft and light while still being strong enough to hold together. Those two qualities, softness and strength, are exactly what a burger bun needs.
Most people judge a burger by the patty. Ask anyone who has eaten a great burger that fell apart in their hands, and they will tell you the bun decides whether the whole thing works.
A burger bun has two jobs that pull in opposite directions. It has to be soft, because a tough bun makes every bite a fight. It also has to be strong, because it is holding a hot, heavy, wet stack of meat, cheese and sauce for the ten minutes it takes to eat.
Most buns choose one. Soft ones disintegrate. Sturdy ones eat like cardboard.
What tangzhong does
Japanese milk bread solves this with a technique called tangzhong. A small portion of the flour is cooked with liquid into a thick paste before being added to the main dough. Gelatinising the starch this way lets the dough absorb and retain far more water than it otherwise could.
The result is bread that is remarkably soft and springy, stays fresh longer, and has a fine, even crumb that compresses under your hand and then springs back rather than tearing.
That last property is the one that matters for a burger. You can press the bun down over a thick patty, it will compact to a size your mouth can handle, and it will not split.
Why we bake ours at dawn
Enriched milk bread is at its best fresh. It stales more slowly than lean bread, but the difference between a bun baked this morning and one baked two days ago is not subtle.
So we bake them in-house each morning. It is the least visible thing we do and one of the more difficult, and it is the reason our burgers hold together from the first bite to the last.
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