USDA zone 10 food forest/ warm temperate

Hi we are finally moving to warmer climate! It's a climate were mangoes and bananas grow.
We want to build a food forest and I want to know three things:
1. which rare and unusual plants can I grow which are NOT fruit? Something I can cook with.
2. What grows under an avocado as it has very dense shade?
3. Which annuals grow well in a food forest? I saw a video were they grew chillies in a food forest but that's about 400 km further North (down under so it's South for you)? Could I grow tomatoes, pumpkin, tomatillo, eggplant, cucumbers etc there?

here is the video link: webpage

I had great results with Seminole pumpkins in the shade.  

I have planted katuk here for the first time.   There's a good chance it can't overwinter here but it's a tropical understory shrub.  I taste tested when planting and it is a very mild flavor in addition to being fast growing and nutritious. Popular in South America, but I don't know how hard it is to get in Australia.

You do have this native plant https://en.wikipedia.org/wiki/Atriplex_semibaccata which I wanted to try here. There's even a fair chance it's wild somewhere near you so you can taste test it without buying the plant.

Chayote is a perennial typical squash that is very popular in Mexico and can reliably be found in Texas grocery stores.  I suspect that could be trained to grow up into avocados and so avoid the problems of deep shade.

We're also at the top of the native range for chili pequin (wild native chili pepper).  The birds have planted it in the dry shade at the back of my yard.  Found them when I identified the ripe berries.  I suspect your best bet would be small fruited varieties like that.  Large peppers probably need more sun to develop to that size.

I have to have a look. Our government in their endless wisdom makes it more and more difficult to import any seeds. Atriplex I haven't tried that because we are moving from a cool and moist environment to a warm and moist environment. But for you it should work perfectly. I had chilacayote in Brisbane and it is a monster. I had problems finding decent recipes for that other than some sweets. Yes and I bought chilli pequin seeds!

I'll keep my eyes peeled for the atriplex.  Generally I will eventually find any plant that catches my eye.  It just may take a few years.

https://en.wikipedia.org/wiki/Chayote

This is also in the gourd family.   I had to look up Chilacayote as I hadn't heard of it.  This is more vegetable than fruit.