Gefilte fish, the butt of many jokes and disparaging comments, is simply a long simmered fish dumpling. It's not particularly glamorous or lovely--the individual pieces are rather lumpy and homely. Nonetheless it's a holiday classic among Jews of Eastern European origin and making it each year has become one of my Passover traditions. If you've ever seen (or worse yet, tasted) gefilte fish out of a jar you may think that's how it's supposed to taste and why bother making it. The homemade variety is altogether different and quite tasty, especially slathered in horseradish.
You need to plan ahead and talk with your fish market to make sure they'll grind fish and provide you with fish bones for the stock. This used to be no big deal but recently, as more and more fish has come from far off places, many stores are unable, apparently by law, to give you bones and trimmings. So call around. Here in the Northwest, I usually use a mixture of salmon, cod, and halibut but you can certainly experiment with your fish varieties. Have the fish market grind the fish for you --the market I use has a grinder that is only used for fish (no shellfish, pork, or other meats) so that takes care of the kashrut issue, at least for our family. Ask them to throw in some onion and carrot while they do the grinding--this will save you work and mess down the road.
Once you get home with your package of ground fish and weird bones and trimmings, the first step is making the stock as seen in the photo below. Note the fin! This is, after all, ethnic cooking.Once the stock is cooked and strained, it's time to dig your hands into all that fishiness and mix in eggs, matzoh meal, salt, and pepper. The small patties are formed and then slipped gently into the simmering stock and cooked for a good long time. Eventually you end up with this:
Your seder guests will be delighted and amazed to have real, homemade gefilte fish which they will happily slather with horseradish and gobble down. It's expensive and stinky to make, but it's a big part of my Passover tradition. If you aren't completely appalled and actually want to try it for yourself (and I hope you will), the recipe is here.
It seems so obvious that I shouldn't have to say it, but .....don't taste the raw fish.