1. Potato's (really depends on how much leftovers you want, I boil 8 to 10 good size Michigan Potato's, I know, use Idaho's or what ever, I like Michigan.
2. Hard boil a dozen eggs
3. 1/2 cup each onions and celery diced fine.
4. 24 oz container sour cream
5. 1 egg
6. vinegar
7. 1/2 tablespoon Black Pepper
In a good size bowl add peeled, and diced potato's, fine dice 6 of your boiled eggs and add to bowl, same with onions and celery. In a double boiler add sour cream and raw egg. Heat sour cream constantly stirring, add pepper when you give your arm a rest from stirring. Heat to almost a boil, when you stick your finger in and it's hot or you see a little steam coming up you are real close. It will not have a silky texture, the nature of the sour cream, no worries. Pull off of double boiler and let rest 2 or 3 minutes. Now here is the to taste part, I add two cap fulls of vinegar, taste, sometimes add another cap, but two is usually good for me. My sisters like 3 or 4 so it's something you have to experiment with. Pour sauce over potato's and mix really well. The eggs in your mix will bring about a little tint of yellow to your mix, then you know your done. Add the extra eggs cut in half on top of your salad and pepper them. Your done. I am a fan of salting when it's on your plate, these will need salt to top them off. These are best when they are still warm from the cooking and are not as volatile as a mayo or mustard base sauce.
Enjoy