The sun is the best stain remover for plastic

The best way to get tomato sauce out of a plastic lunch box is to stop scrubbing and leave it in the sun.

Scrubbing usually makes it worse. Tomato stain is lycopene, an oil-based pigment that seeps into the pores of the plastic. Hot water and aggressive scrubbing just push it deeper — and heat can actually set the stain permanently.

The right order: wash normally with cold water and dish soap first. If a faint stain remains, mix baking soda with a little water into a paste, rub it on, let it sit for 15 minutes, and rinse.

Then the real trick: put the lid and container in direct sunlight for a few hours. UV light literally breaks down the red pigment. It’s the only thing that reliably removes the stain, and it costs nothing.

If you’re in a dark-climate rut, a soak in hydrogen peroxide (the 3% stuff from the pharmacy) for a few hours works too. But the sun is the honest answer here.