Poland
Thin smoked Polish sausage sticks, commonly sold as snacks.
Poland
I would put Pierniki gingerbread on the list for Poland because it is the kind of thing that feels useful once you are home, not just another airport purchase. Biscuits and dry breads are good because they survive the journey and are easy to share at work or with family. The reason it works is that it gives you a quick reminder of the trip without needing to keep a fragile ornament safe forever.
Kitchen gadget for making Polish dumplings at home.
Poland
When I think of an easy, crowd-pleasing thing to bring back from Poland, bison grass vodka is a good pick because it does not need much explanation when you hand it over. For alcohol, I would only bring this back if it is sealed properly and comfortably within the UK allowance; otherwise it is better as a UK-buy link. I would rate it higher when it is locally made, clearly labelled and easy to use at home, and lower when it is just tourist packaging.
Poland
This is exactly the sort of thing I like bringing back from Poland: small enough to fit in a bag, but specific enough to remind you where you bought it. The best version is usually the sealed jar, tin or packet from a normal supermarket, spice stall or food hall, not the most expensive tourist version. 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.
Poland
Oscypek smoked cheese is worth adding because it feels like something you actually noticed while travelling through Poland, rather than a generic souvenir. This is more of a buy-in-the-UK idea now unless current food rules clearly allow it. It still belongs in the database because people search for it after tasting it abroad. The ideal version is modestly priced, not too bulky, and good enough that you would buy it again even without the holiday memory.