pre-workout food is doing my head in

Basically I've tried everything at this point. Training on empty — felt strong for about 10 minutes then hit a wall. Big meal an hour before — spent half the session feeling sick doing burpees. Right now I'm landing on something small about 45 mins before, usually just some oats or a bit of fruit, and honestly it seems to be the difference between a session that goes somewhere and one that just... doesn't. I've also been having matcha before instead of coffee because it doesn't spike me the same way. To be fair I was sceptical but I don't get that jittery thing mid-set anymore. Mind you I'm still figuring it out. Some nights the kids go down late and I'm training at 10pm on whatever I had for tea three hours ago. You just adapt don't you.