I have a lot of cookbooks. Every now and then I weed some out for garage sales or the like. But by a lot, I mean probably 300. I was going through some today and found one that just had the most vile recipes imaginable, yet I've still kept it. (It was a gift.)
My worst cookbook (that I've found so far) Is the Taste of Home Quick Cook Cookbook from 2000.
This is the one that has a recipe for a taco shell, lined with a slice of american cheese, add a cooked hotdog, then top with canned baked beans.