Grandma's Potato Salad

This recipe may as well be holy writ in my family.  Grandma's potato salad is legendary, and is spoken of with almost a hushed-like reverence. (And a bit of drool.) 
It is actually my Great-Grandmother's recipe who passed it down to my Grandmother, who used to make it with my Mother and Aunt.  The last time my Grandma made it was probably the mid-80's.  After she passed away it was a long time before anyone in my family attempted to make it.  When they did it was a bit of a matter of trial and error.  You see, Grandma never wrote it down.
Between my Mother and my Aunt they eventually were able to work out the formula and my Aunt sent us an email back in 2005 with the directions.  The problem was, it was a bit difficult to pass on as the directions were a bit vague, asking for a "squeeze" of this, and a "slosh" of that, and a lot of "until it looks right.
This Easter I tried to work out a more concise version to put to paper.  It was difficult, because there are so many variables to work with, but I think I've gotten it down.  Still, there are a lot of areas that can be tweaked as you go according to personal taste as well as how much bacon fat renders, how large the eggs are, etc.
So here it is in all its glory (you may want to kneel):

Grandma's Potato Salad

1 lb. bacon (use good bacon and use 1 full pound.  I like Farmland brand.)
3 lbs. mid-size red potatoes.  (Grandma made 5, but would also need to make another batch of dressing sometimes because the potatoes really soak it up. I think 3 works perfectly.)
1 small onion, chopped
6-8 eggs

1/4-1/3 c. white vinegar
1-3 tsp. sugar
1-2 Tbsp. flour (possibly)
1 Tbsp. prepared mustard
4 hardboiled eggs, chopped
2-3 ribs celery, chopped small
1/4 of a green pepper, chopped small (optional)

1.  Boil potatoes in their skins until a fork goes in, but don't overcook.  Let cool completely.
2.  Fry bacon, reserving bacon fat.  Crumble drained, cooled bacon.  Strain the bacon fat to remove dark, overcooked bits.  Lightly wipe any burned bits out of the pan.
3.  Return a small amount of fat to the pan and saute onions until just limp.  Remove onion.
4.  Return all remaining bacon fat to pan and heat on (very) low.  Add 2 Tbsp. vinegar to thin a bit.
5.  In a separate bowl, lightly beat 6 eggs. Add about one egg's worth at a time to the warm fat in the pan, stirring constantly with a whisk to avoid cooking the egg before it's incorporated with the fat.  Keep adding eggs as needed, but not more than you have enough fat to incorporate, usually between 6-8 eggs.  (My magic number was 7.)  It will have a thin, foamy texture.

 6.  Keep stirring constantly and raise the heat slowly until the mixture starts to thicken.  (My heat settings go from low, then 2-9, then high.  I started on low and raised to a 3.)  Do not get to high or eggs will start to scramble, if this happens, remove from heat immediately and whisk vigorously.  The mixture reaches desired consistency when you can leave a trail with a spatula.  (If it still is too thin, you can add flour to thicken.)

The eggs almost scrambled while I tried to get this picture!

7.  Add remaining vinegar a Tbsp. at a time to taste, and add sugar a tsp at a time to balance sweetness.  Add mustard, and salt & pepper to taste.  Stir until well incorporated and seasoned to taste.  It should have a fairly strong sweet & sour flavor.  It will not be as strong once it is on the potatoes, so don't be afraid of a strong tangy taste.
8.  Allow dressing to cool slightly.  Peel potatoes and slice potatoes about 1/4 in. thick.
9.  Mix dressing, onion, crumbled bacon, chopped hard boiled eggs, celery and green pepper with potatoes until combined.  Add more salt & pepper to taste, if necessary.
It is best served cool, but not cold, so if you need to refrigerate before serving, take it out of the refrigerator about 20-30 minutes before dinner.  Stir before serving.

I think Grandma would be proud.

source:  Diana B.