Here in the sweltering Languedoc I am labouring away at my desk nourished by birdsong and the knowledge that Chef Lander will be putting all sorts of delicious things on the table under the chestnut tree.   It’s too hot to eat much so we are concentrating, at lunchtime anyway, on the great local produce pretty much unadorned. On Sunday afternoon we were sipping a bone dry Lorentz Riesling Kanzlerberg 2002 Alsace Grand Cru - fully mature and chock full of extract though only 12.5 per cent alcohol. On the table were slices of the juiciest little round melons bought from an old man in the next village who cannily sets...