Portugal
This is exactly the sort of thing I like bringing back from Portugal: small enough to fit in a bag, but specific enough to remind you where you bought it. Tins and sealed products are the easiest version. Fresh or chilled fish is usually not worth the hassle unless you have checked the rules. It is also the kind of thing you can talk about when someone asks what you brought back, because there is usually a little story attached to where you found it.
Vietnam
This is exactly the sort of thing I like bringing back from Vietnam: small enough to fit in a bag, but specific enough to remind you where you bought it. Tins and sealed products are the easiest version. Fresh or chilled fish is usually not worth the hassle unless you have checked the rules. It is also the kind of thing you can talk about when someone asks what you brought back, because there is usually a little story attached to where you found it.
Sambal tahai is worth adding because it feels like something you actually noticed while travelling through Brunei, rather than a generic souvenir. Tins and sealed products are the easiest version. Fresh or chilled fish is usually not worth the hassle unless you have checked the rules. The ideal version is modestly priced, not too bulky, and good enough that you would buy it again even without the holiday memory.
Maldives
Crisp tuna snack or dried fish product associated with island cuisine.