I recommend Galantamine. Its not a food but a supplement. You can purchase it via Internet. Also Ginko Biloba is said to be helpful in promoting and inducing lucidity.
Things like fresh fruit/juice have been shown to help. If you’re just vegetarian and not vegan, I as well as others have noticed milk can really make a difference for recall.
I’m pretty new to this stuff too, but after reading online and talking to some fellow enthusiasts, I’ve heard a lot about vitamin b, but more specifically Tryptophan. I read somewhere that this was what made a lot of people have more vivid dreams, and you can find it in (mind these results are highly reliant on google) Eggs, soybeans, cheese, milk, bananas, and potatoes to name a few. Hopefully that works for you, because it’s definitely helping me!