Diced onions and peppers freeze fantastically as long as you plan to use them in a sauce or soup. For some veg it’s also better to buy frozen if you’re not planning on eating it raw or cooking it immediately, like broccoli. Jesus Christ, never let broccoli rot. I’m pretty sure some corpses smell better.

Allegedly washing and drying veg also makes it last longer, but I always feel like if I made it that far I might as well just prep and store it.