I just made a batch of these and they do NOT taste like the ones I had yesterday at the fair.  The potatoes, onions and bell pepper didn't break down like at the fair and the flavor was off.  So, I will play with it a bit.
        The potatoes need to be shredded so they dissapear in the mix. Have to do something with the onions and bell pepper too because you do not "see" them at the fair.   Perhaps potato buds, granulated onion and no bell pepper.  8/23/09

California State Fair Tacos Recipe
Growing up in Sacramento, the California State Fair was always a great treat.  It was on for about ten days and we would take a bus or walk a few miles over to it and spend the day, every day.  Spike Jones, Mel Torme great shows and fun food. Especially for a 9-14 year old kid in 1958 through 1955. Then after we moved back to Carmichael and I was raising Black Angus steers in 4-H I showed my steers at the State Fair. So, I slepet there too in '55 and '56.
    One of the treats was a soft taco stand across from the grandstand main entrance.. The same people are still selling their soft tacos at the new California State Fair. As they have since 1948.
For the past few years I’ve been trying to figure out how they make them. Then, this year, after having a few, I decided to see if I could find a similar recipe on the computer.
  Ha!  There was what looks like THE recipe. And, here it is.  
     Since it is in the  computer and available for the whole world to see, I guess I can include it here.  In the computer it said  by the goldminer but I can’t find anything about the gold miner and recipes.   I’ll keep looking so I can give proper credit..
These tacos are a copy of the soft tacos featured at the California State Fair
2 lbs.        hamburger
1  head     iceberg lettuce, shaved and cut into strips 1 inch or less.
1                yellow onion, diced
2               regular potatoes, peeled and diced to about 1/4 inch  (8/23/09-that didn't work)
2  tsp.      granulated garlic
2 small cans   diced green chilies, drained
1               green bell pepper, seeded and diced like the chilies and potatoes
1  1/2 tsp.    salt
1t            ground pepper
Corn Tortillas
La Victoria's Taco Sauce (Mile, Mediun or Salsa Brava.)

   I usually cut this in half.....
1. Peel, cut potatoes and boil. Once cooked, chop into small pieces about 3/8 inch. Set aside.
2. Cut head lettuce in half. Using sharp knife shave lettuce as thin as possible. Once cut into strips, cut into 1 inch long pieces. Set aside.
3. In a deep pot add 1 cup water then add hamburger breaking it up as added. As hamburger cooks use a wisk to stir breaking up hamburger into BB size pieces. Let hamburger cook. Once cooked, drain.
4. Once drained place in a large fry pan. Add 1 1/2 cups water. Add salt, pepper, granulated garlic and mix well. Add chopped onions, chilies, green pepper, stir and mix well. Allow to cook 10 minutes on medium high.
5. Add potato, stirring and mixing well.
6. Add lettuce, stirring and mixing well. Add another cup of water, mixing well and allow to cook 10 minutes. .
7. To cook tortillas barely rinse one side under water. Place on a Styrofoam plate and microwave 12 seconds (1300 watts).
8. Add meat and sauce and roll up. You have to hold one end pinched closed so it doesn’t fall out.
9. For a variation add shaved lettuce on meat and sauce.
10. The taco best suits thin sauce. I pour out half of the sauce and then add water and shake.