Grown in Europe and the US, hazelnuts are encased in a smooth, hard brown shell but are most commonly sold shelled. The sweet-tasting, cream-coloured kernel is small and round, with a pointed tip. Its thin, dark brown skin is faintly bitter, so some people like to remove this before eating.
Also known as cobnuts or filberts, hazelnuts are good eaten raw but the flavour takes on a more mellow, sweeter character when they are roasted. Like almost all nuts, they have a high fat content, which means they’ll go rancid pretty quickly if not refrigerated.
Hazelnuts in their shells look good, but they will go rancid more quickly. Ready-shelled nuts in airtight packaging last longer.