Pack the heavy stuff on the bottom

The trick to keeping a sandwich from getting flattened in a lunch box is to pack the heavy stuff underneath it and give the sandwich a rigid container.

Most flat-sandwich tragedies come from an apple or a juice box sitting on top of it for three hours. Gravity is undefeated. So pack the weight at the bottom of the lunch box — yogurt, fruit, drink — and lay the sandwich on top. If you’re using a vertical lunch box, it needs to stay upright, but that alone solves most of the problem.

The other fix is a hard-sided container. A small Tupperware, a bento box, or a dedicated sandwich keeper gives it structural support that a Ziploc bag simply can’t. Cardboard and plastic wrap are not load-bearing. If you don’t have a hard container, improvise: put a flat plastic lid or a stiff piece of something on top of the sandwich inside the bag, so the crushing force spreads out instead of punching through.

One more little trick: toast the bread. It holds up way better against moisture and pressure. A soggy, flattened sandwich is worse than a stale one.

Your sandwich doesn’t need to survive a construction site, just a commute.