Nostalgia is the watchword for this collection of ""Mrs. Witty's"" personal favorites, many of them remembered from her California childhood or gratefully received from long. ago editor Ann Batchelder through the pages of the Ladies' Home Journal. Though Witty gets as cosmopolitan as orzo ""risotto"" and preserved lemon, she sticks mostly to such good old American food as pot roast, sirloin steak, plain steamed lobster, pineapple upside-down cake, baked beans, a mild (though newly beanless) chili con came, and--with much advice and ado on how, what, and why--real mashed potatoes. But (unlike, say, Jane and Michael Stem) Witty doesn't just pass on received recipes selected only for their age and comfortable associations. She has to like a dish to start with; she takes care to work out kinks and find the yummiest versions; and when she introduces one of her own or her family's improvements--never fussy, always sound--you can be sure that it will work.