By Liam Gilliver Brits love their spuds – but using them up before they start sprouting is no easy feat. Whether you’re a home-made chip fanatic, love nothing more than a dollop of mash, or often daydream about the humble Jacket Potato for dinner – nobody wants a green, wrinkly, mouldy-smelling spud. However, supermarket giant Tesco says the nation’s favourite vegetable (yes, tats are a vegetable) actually have a ‘great shelf life’. In fact, potatoes can stay fresh and firm for up to six months by following a few simple steps – so you’ll always have a few roasties at hand. It’s an easy way to …