The soggy-sandwich fix is a divider, not a fancy lunch box

Keeping a sandwich from getting soggy is mostly a packing problem, not a lunch box problem — the real move is keeping the wet stuff away from the bread until you’re ready to eat.

Any cheap bento-style box with a leakproof divider does the job. Bentgo, Sistema, whatever — they all work. Want to save money? A tiny container or silicone muffin cup inside a normal lunchbox is the same trick. Put the tomato and avocado on the side, assemble at lunch, and you’re done. That’s the whole secret. The sandwich will be as good as it was at 7 a.m.

If you’re determined to build the sandwich in the morning, then play defense. Spread butter or mayo on both slices of bread — fat is a moisture barrier. Pat your tomato slices dry with a paper towel before laying them on. And don’t put the tomato against the bread; tuck it in the middle, between cheese or meat or a lettuce leaf. Hearty sourdough or rye also shrugs off moisture way better than fluffy white.

Avocado is its own problem because it turns brown and slippery. Best approach: mash it in a small container with a little lime juice and spread it at lunch. Or just wrap a half with the pit still in — it’ll survive.

The “best” lunch box isn’t the expensive one. It’s the one that keeps the tomato far away from the bread until you’re eating.