To make quenelles, grind pike in food processor, or use a tamis if you have one. Set aside.
Bring water to a boil. Sift in flour and stir until water is absorbed. Keep stirring so that mixture doesn't stick to pan. Remove from heat and beat in one of the eggs. Cool mixture, then refrigerate until cold. Remove mixture from refrigerator and blend it in food processor until smooth. This is the panade.
Cream butter in small bowl. Put ground pike in bowl that is set inside another bowl of ice. Season with salt and pepper, mix in panade and gradually add other whole egg and all egg yolks. When blended well, add butter. This can be done in food processor if all ingredients are kept cold. Chill mixture for 30 minutes.
To make white sauce, place chicken stock in heavy saucepan over medium heat. Bring to simmer, then reduce heat and continue to simmer on low until stock is reduced down to 1 cup liquid, about 45 minutes.
In large saucepan over medium heat, reduce cream until it begins to thicken, whisking occasionally.
Whisk thickened cream into stock, adding more or less cream, depending on desired consistency.
Season with salt and pepper to taste. Strain sauce through a fine-mesh sieve, if desired.
Makes 2 cups.
To assemble dish, shape quenelles by mounding mixture between 2 warmed spoons. Set each quenelle on floured surface.
Preheat oven to 200ºC . butter baking dish large enough to hold quenelles. In wide saucepan, bring 3 litre of water to a boil and poach quenelles for 15 minutes without letting the water boil. Drain thoroughly.
Arrange quenelles in prepared baking dish.
Nap quenelles with enough white sauce to cover. Sprinkle with parmesan cheese. Bake for 15 to 20 minutes, until the cheese browns.
Serve 2-3 quenelles per person.