First of all, you have to preheat your oven to around 375 degrees Fahrenheit. After that, boil some water in skillet and blanch the head of cabbage in it for around five minutes. After boiling the cabbage head, place it in cold water. Then, take out the outer leaves and put it in the boiling water again so that the inner leaves become soft. Now, dry the cabbage by putting it on a towel.
Take a small bowl and put the matzoh meal in it. Add one cup of stock and soak it well. Meanwhile, heat the olive oil in a small skillet and sauté the onions for around four to five minutes over medium heat. Remove the skillet from the stove before the onions become brown.
Take a wooden bowl and chop the fish in it by using a sharp knife. Add the chopped onion, egg yolks, 2 teaspoons of salt, white pepper, and cayenne, the chopped parsley and tarragon.
Take a clean medium bowl and whisk the egg white until it becomes firm (but don’t make it stiff). Then, put the fish mixture into the bowl and mix all the ingredients well with each other.
Taste the mixture, if there is a need to add something, do it now. Take the leaves and put the fish mixture in them after dividing it into portions.
Place the filled leaves on the baking sheet and bake them for around half an hour. Serve them with some salad and cold drinks.