While we are on the subject of Huevo Limon for Passover, Nona also made a Huevo Limon soup called Agristada. I was asking my sister Carole about it and she said it is her favorite comfort food to this day.
The creamy looking lemon soup reveals little parsley and ground beef meat balls floating just beneath the surface. This may be an acquired taste but once initiated it is delicious.
To make this lemony soup you need:
1 pound of ground chuck meat
2/3 cup chopped parsley
½ cup matzo meal
Salt and pepper
1 and ½ cups cold water
1 egg yolk
1 tablespoon matzo cake meal
Juice from 1.5 to2 lemons (depending on how juicy they are and your taste)
Salt and Pepper
Combine the ground chuck, parsley, eggs, and matzo meal in a mixing bowl. Season the meat ball mix with salt and pepper to you taste. Roll little round meat balls in your hands and place them on a sheet of waxed paper. Heat a non stick skillet and cook the meatballs until they are seared golden on the outside and cooked through. Set them aside while you prepare the soup.
Beat the eggs with the egg yolk in a small bowl. Add the lemon juice and then the cake meal and whisk until smooth. Bring the cold water to boil in a large saucepan. Take 2 tablespoons of the boiling water and add it to the bowl with the eggs and lemon. Whisk rapidly to heat the eggs with the hot water. Add two more tablespoons of boiling water, whisk again. Next add the eggs and lemon right back into the boiling water and whisk to heat. Do not let the water, egg, lemon mixture come to a boil. Keep whisking while it simmers and it will become thick and smooth… Do not boil. Add the cooked meatballs to the soup and season with salt and pepper. Serve with chopped parsley sprinkled on top. 
I don’t think I would serve this to a large crowd since it is tricky. Make it for yourself for lunch or when you have no guests. Enjoy your little secret treat.