415g for £1.00 = 24p per 100g (Morrisons) 675g for £1.45 = 21p per 100g (Tesco) Typical "Best Before End" from date of manufacture is around 1 year (in reality even longer), so these will last for a long time if you don't eat much of the stuff.
Or just buy the Lidl own brand (tastes and looks absolutely identical - probably made by Nestle) at 89p for 625g as a standard price. Why waste money on a brand - and particularly one as toxic as Nestle?
415G at Morrison's for £1. Depends how much of the stuff you eat I suppose. Voted hot.