It was almost certainly Guano, Bat droppings collected from caves. The fruit bats barely digest the berries they eat & this makes it edible for humans.

Looks like Pollo Tropical to me but I could be wrong.

I was never really good at geography, nor history in general. Good thing this movie relates to me in other ways or else, I probably would not have enjoyed Indiana Jones period.
THERE IS NOTHING TO FEAR. COLLEGE FOOTBALL IS HERE!!!

"Hong Kong club"? Try "Shanghai club" aka Obi Wan.

That is actually a very good question. I will watch it again and report back.
THERE IS NOTHING TO FEAR. COLLEGE FOOTBALL IS HERE!!!

You would have to be more specific. At the beginning of the film, they were not served anything. Indiana and Willie were both in that Hong Kong club.
I think he's talking about the village,
before
they start trekking to the temple.
Willie: "I'm not hungry."
Indy: "You're insulting them. And you're embarrassing me. Eat it."
That scene.

You would have to be more specific. At the beginning of the film, they were not served anything. Indiana and Willie were both in that Hong Kong club.
If you are writing about the temple part: snake surprise (snake with what look to be eels coming out), some kind of beetle bug, bugs on a leaf, eyeball soup, and everyone's favorite dessert, chilled monkey brains!
Looks across the table at you
What?! Not eating?
THERE IS NOTHING TO FEAR. COLLEGE FOOTBALL IS HERE!!!

I don't know, but it looks like Willie is also getting a fly along with the mouthful she takes. It keeps buzzing around the turd on the banana leaf, and she tries to shake it off. But it is persistent, and seems to disappear in her mouth as she puts the food in her mouth.