Butter is your sandwich's raincoat

The trick to a non-soggy sandwich is keeping wet things away from bread until you’re ready to eat.

The easiest fix is a barrier. Spread butter or mayo on both slices of bread, all the way to the edges. Fat repels moisture from tomato, pickles, and lettuce. This is the single most effective thing you can do — more than any fancy lunchbox insert.

Next: don’t let wet ingredients touch bread at all. Tomato and pickles go between the meat and cheese, not against the bread. Even better, pack the wet stuff in a tiny separate container and assemble at lunch. It takes twenty seconds and changes everything.

A couple other hacks: lightly toast the bread, toss a paper towel in the box to catch condensation, and don’t store the sandwich next to an ice pack if you can avoid it. Moisture always finds the bread eventually.

Future you at noon will be grateful.