In Forever Summer With Nigella, Nigella Lawson is, of course, the British Sophia Loren of linguine, a curvy cook whose shows are shot in soft-focus with woozy world-beat music on the soundtrack. With her tight sweater wobbling over a bowl of ''a very rough-and-tumble salad'' and her guttural purrs about ''six egg whites... whisked until they're gleamy and satiny,'' Nigella demonstrates clearly explained, reasonably simple meal making, but she also delivers the kitchen version of a ''Penthouse'' Forum letter come to life.
Enough of a writer herself to have scored a column in ''The New York Times,'' Lawson is all about the adjectives on this new ''Forever Summer'' series. Chocolate shards are ''cratery splinters''; Japanese cold noodles are ''that slippery tangle''; ever the harsh mistress, she commands us, when making a meringue, to add the sugar ''serenely, slowly, unworriedly.'' Yes, ma'am.