Wilja is nowadays quite a well-kept secret among discerning housekeepers and chefs – having been dumped by the supermarkets in favour of Estima in the 1980s.  It is another general purpose white like Estima, but with a waxier texture, a rougher skin and a stronger flavour.  Wilja taste of the soil they grew in, and because of their waxiness, they don’t easily break down when boiled for a few minutes too long.  Good for putting in pies and pasties, Wilja makes a medium-to-heavy mashed potato