Sunlight is your best bet for tomato-stained plastic.

Sunlight is the most reliable way to get stubborn tomato stains out of a plastic lunch box.

Tomato stains are oil-based. That’s why soap and water stop cutting it once the stain sets. Make a thick paste with baking soda and a little water, rub it over the stain, then leave the container in direct sunlight for a few hours. The UV breaks down the red pigment that normal scrubbing can’t touch.

No sun? A soak in hydrogen peroxide works too. Just test it on a small spot first and dilute it if you want to be careful. And skip abrasive scrub pads — scratched plastic just gives the next stain more places to hide.

Stains are ugly, but they’re not dirt. Let the sun do the deep cleaning.