It's spicy spreadable salami and definitely happiness in a jar. I've had it tossed in pasta and spread on a baguette and it's delicious both ways. I've bought it at La Bottega.
As mentioned above, La Bottega has nduja in jars but they sometimes have the Nduja di Spilinga imported from Italy in the casing like a salami (at the deli counter). It's the one you should have if you want to try it. It's the one you will see all over Calabria.
I second the 'nduja Di spilinga recommendation, I've had it a number of times now thanks to a Calabrian connection and it is fantastic, not like the potted stuff. The rendered fat from it is pure gold, amazing flavour.
Francis
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