The question isn’t really about where to buy it, but which version to buy. The most famous brand is from PICK, and you can buy this mostly in grocery stores and fore sure in the Great Market Hall in Budapest. I suggest you visit the Market Hall, and then you can look around elsewhere as well. What is great about the market hall is that you can often ask for a taste of the different salami versions they have on their desks, and thus you can taste and buy a version you like based on that.
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