Keep wet sandwich fillings off the bread

The fix is to keep tomatoes from touching the bread until you’re ready to eat.

Your real enemy is moisture sitting directly on the crumb. Tomatoes, pickles, cucumbers — anything with high water content will soak into bread within a few hours. So you have two options: build a barrier or pack separately.

Simplest barrier is a spread. Mayo, butter, cream cheese, even hummus — if you coat both slices down to the edges, it seals the bread and stops the tomato juice from soaking in. It also adds flavor, so this is the easy win.

If you’re avoiding spreads, use a dry buffer leaf of lettuce between the tomato and the bread, or tuck the tomato between two slices of cheese or meat so it’s not directly against bread. And toast the bread or use a denser loaf like sourdough — it survives better.

Also, you can just pack the tomato slices in a little container and slap them on at lunchtime. That’s the nuclear option and it always works.

You don’t have to choose between crunchy bread and a tomato slice. Just don’t let them meet too early.