INGREDIENTS

Buyer's guide

Gruyère is at its best from mid-November to mid-April. Swiss gruyère - labelled as Le Gruyère Switzerland is protected and will have the word ‘Switzerland’ stamped in red across the top and bottom of its rind. If you prefer a milder flavour, look for gruyère doux, which will have been matured for around five months, rather than gruyère vieux, which can be aged for up to 18 months.