There is no single best bread — the right choice depends on the filling. Sturdy, open-crumbed breads like sourdough are ideal for heavy, saucy sandwiches such as steak or pastrami because they hold up without going soggy. Soft, slightly sweet breads like brioche suit richer or more indulgent builds, like a beef patty or a tuna melt, where you want a tender bite. What matters in every case is that the bread is fresh and, ideally, toasted, so it has structure and a little crunch. At Sandwich Lab we build on both sourdough and brioche and match each one to the sandwich it serves best, rather than using a single loaf for everything.

Toasting does two important jobs. First, it firms and slightly dries the surface of the bread, creating a barrier that resists the moisture from sauces, tomatoes and juicy fillings — which is what keeps a sandwich from going limp before you finish it. Second, the heat triggers browning reactions that develop deeper, nuttier, more savoury flavour you simply cannot get from untoasted bread. Toasting also adds textural contrast: a crisp exterior against soft, warm fillings makes every bite more interesting. The catch is timing, because toasted bread is at its best fresh, which is why we toast to order rather than in advance. Done right, toasting is one of the highest-impact steps in the whole build.