Potato kugel from Kosher By Design
Spice and Spirit probably is overall my dirtiest cookbook. The binding is totally off.
I used to call it the purple cookbook, but since the cover is gone for some time now, I can't. Don't get me started on the index. I think I have until D.
Ha ha! I also call it the purple cookbook! I actually had an extra brand new one sitting in my closet for many years (double engagement gift). I ended up givingi t to one of my sisters when she commented that she didn't know what the purple cookbook was. But as mine is s-l-o-w-l-y fading away I sometimes regret that I didn't pass along the used one! But whenever I have that thought I feel guilty for thinking that way!
And it's out of print, ladies
My dirtiest page is the one-bowl chocolate cake in Classic Kosher Cooking (Sara Finkel). My purple cookbook was always too large to have on the counter with the mixer in my previous apartments. So it was somewhat protected.
This thread reminds me of a story. A mother had to go away for a week and had her friend stay with her children. They were picky eaters, but when the mother came home the kids told her that all the meals were great.
She asked her friend "how did you get my kids to love what you made?"
The answer "I just went through your cookbooks and made the recipes from the dirtiest pages!"