In my experience, even better than a 30 minute nap is a 15-30 minute Non-sleep Deep Rest (NSDR) or yoga nidra session (popularized by Andrew Huberman). It's a guided meditation of sorts where you do a body scan; as the narrator names different body parts you place your attention on the sensation at that body part. By occupying your mind on physical sensation, in conjunction with slow, deep breaths, you're able to consistently and efficiently achieve a relaxed, restful state.

So at noon I set my slack status to avocado emoji "eating lunch," pop a caffeine pill, then lay down with an eye mask and noise cancelling headphones for half an hour while an Australian woman tells me what to feel.