What defines this burger is the ratio, not any single component. It is a large beef patty on a five-inch bun, a bun deliberately wider than the standard burger roll, so the bread footprint is built to extend past a thin, broad patty rather than ride on a tall compact one. That width is the design decision everything else follows from. A bigger, flatter bun changes how the cold garnish is distributed: mustard, lettuce, tomato, pickle, and diced onion spread across the full face instead of being concentrated in a small stack, so every bite gets the acidic and crunchy layer rather than a few central bites carrying it all.
The craft is in matching a thin griddled patty to that wide soft bun without the structure failing. The patty is cooked flat on a flat-top so it covers the bun rather than doming in the middle, and mustard is applied directly to the meat side, where its acidity cuts the beef fat at the point of contact instead of sitting away from it under a layer of bread. Lettuce and tomato are the cool, wet counter, and the diced onion is set in among them for a sharp, even crunch rather than a single ring that slides out on the first bite. The bun is soft and yielding so it compresses to the patty under the hand rather than fighting it, which is the same reason a soft bun is chosen for any griddle burger, scaled up to a larger footprint. The whole assembly is built to be ordered with components added or removed freely, which is why the cold layer is arranged as a system rather than a fixed stack.
The variations are mostly additive on the same wide chassis. Cheese, bacon, jalapeños, or a doubled patty each change the weight and the balance without changing the underlying bun-to-beef geometry. Shrinking it onto a small roll turns it into a different, more compact burger and loses the broad-footprint logic that defines this one. Those builds deserve their own articles rather than being crowded in here.