Your lid is lying to you.

The easiest way to find out whether your lunch box leaks is to fill it with water, close it, and turn it upside down over the sink.

That test exposes the real problem, which is almost always the lid. Those plastic click-lock containers with the little flaps are the worst offenders. The latch feels reassuring, but the gasket inside is thin, and once it wears or shifts, soup finds its way out.

For soup, the fix is a wide-mouth thermos with a screw-on lid and a silicone gasket. It’s a food jar, not a lunch box, and it’s designed to hold liquid upright for hours. For yogurt, a glass jar with a screw lid works the same way. Both beat any latch design.

Two more things: don’t overfill, leave an inch of headspace so sloshing doesn’t pressure the seal. And if it’s going in a backpack, drop the container in a Ziploc bag anyway. That’s not the fix, that’s insurance so your bag doesn’t smell like lentil soup for a week.

Your backpack will thank you.