what do you actually eat before a session

Been trying to sort my pre-climb nutrition properly for a while now and honestly I'm still not sure I've cracked it. For years I just kind of... ate whatever was around and then showed up at the wall. Sometimes that was fine, sometimes I'd be three moves into a project and already feel like my arms were full of cement. Right now I'm on a banana + whey shake about 45 minutes before, sometimes with a bit of matcha stirred in because I find it keeps me sharp without that jittery edge you get from straight caffeine. But I'm genuinely not sure if that's the right window, or if the shake is even doing much at that point. Like maybe I should be eating more actual food an hour and a half out instead. I've seen people at my wall eating rice cakes, peanut butter on toast, even just a big bowl of oats. One lad was eating cold pasta once which, fair play, but no thank you. I'm mostly sport climbing these days so sessions are pretty intense, not long drawn out bouldering where you're standing around half the time. Anyone got a pre-session routine that actually works for them? Especially curious if anyone's cracked the timing side of it.