America's Best Lost Recipes: 150 Heirloom Recipes Too Good to Forget by The Editors of Cook's Country Magazine
I was going through one of those phases where I'm entirely unsure of myself and this whole cookbook nonsense and I may as well burn all of the ones I own (except the Thomas Keller nonsense I got for my birthday--it won't burn, it's too pretty) when I came across a reference to this cookbook. Apparently they held some sort of 'lost recipe' drive resulting in a collection of recipes that may not have been published otherwise. Just hearing about this book made me remember why studying cookbooks could be incredibly interesting and possibly very important, both culturally and historically. And it's by the guys who do Cook's Illustrated, so you know the recipes work.
Go buy this book and then go hug your grandma.