Fix a small, daily annoyance
Someone who "needs nothing" usually has one small thing that bugs them every day: a slow coffee maker, a dull kitchen knife, a messy pile of recipe cards. Fix that one thing and they'll think of you every time they use it.
Something they'll use up
Good coffee, nice olive oil, or a treat they'd never pay for themselves. It gets used up, so there's nothing extra to find room for.
A better version of something they already have
They tend to buy the cheap version of things for themselves. A gift that upgrades something they use all the time, like a real chef's knife or good headphones, means more than something new they have to store.
Write down what they mention
"They need nothing" feels hard because it's easy to forget what they said they wanted months ago. Kept keeps a note of it, so the next gift comes from something they said in March, not a rushed guess in December.