PreparationFor sauce: Stir cucumber, mayonnaise, horseradish, parsley, and chives in medium bowl to blend. Season sauce to taste with salt and pepper. DO AHEAD: Sauce can be made 1 day ahead. Cover and refrigerate. For fish cakes: Line large rimmed baking sheet with plastic wrap. Heat 3 tablespoons oil in heavy large skillet over medium heat. Add carrots and leeks. Saut233 until soft but not brown, about 15 minutes. Cool in skillet. Beat eggs, matzo meal, coarse salt, and white pepper in large bowl to blend. Stir in carrot mixture. Place whitefish and salmon cubes in processor. Using on/off turns, chop fish to coarse paste (small pieces of fish will remain). Stir fish into matzo meal mixture. Using wet hands and about 1/3 cup for each, shape fish mixture into sixteen 1/2-inch-thick cakes. Arrange on prepared baking sheet. DO AHEAD: Can be made 1 day ahead. Cover with plastic and chill. Add enough oil to 2 heavy large skillets to coat bottom. Heat oil over medium-high heat. Add 8 fish cakes to each skillet. Sauté until golden and cooked through, about 3 minutes per side. DO AHEAD: Can be made 2 hours ahead. Transfer to another baking sheet, cover, and refrigerate. Rewarm uncovered in 350°F oven 10 minutes. Arrange 2 fish cakes on each plate. Spoon sauce over or alongside. Garnish with lemon wedges and parsley. What to drink: A Chardonnay would be delicious with the haroseth and the salmon and whitefish cakes. We like the apple, pear, and vanilla notes of the Baron Herzog 2006 Chardonnay from Herzog Wine Cellars on California's Central Coast. It's a great kosher wine and a good value at $13.
PreparationFor sauce: Stir cucumber, mayonnaise, horseradish, parsley, and chives in medium bowl to blend. Season sauce to taste with salt and pepper. DO AHEAD: Sauce can be made 1 day ahead. Cover and refrigerate. For fish cakes: Line large rimmed baking sheet with plastic wrap. Heat 3 tablespoons oil in heavy large skillet over medium heat. Add carrots and leeks. Saut233 until soft but not brown, about 15 minutes. Cool in skillet. Beat eggs, matzo meal, coarse salt, and white pepper in large bowl to blend. Stir in carrot mixture. Place whitefish and salmon cubes in processor. Using on/off turns, chop fish to coarse paste (small pieces of fish will remain). Stir fish into matzo meal mixture. Using wet hands and about 1/3 cup for each, shape fish mixture into sixteen 1/2-inch-thick cakes. Arrange on prepared baking sheet. DO AHEAD: Can be made 1 day ahead. Cover with plastic and chill. Add enough oil to 2 heavy large skillets to coat bottom. Heat oil over medium-high heat. Add 8 fish cakes to each skillet. Sauté until golden and cooked through, about 3 minutes per side. DO AHEAD: Can be made 2 hours ahead. Transfer to another baking sheet, cover, and refrigerate. Rewarm uncovered in 350°F oven 10 minutes. Arrange 2 fish cakes on each plate. Spoon sauce over or alongside. Garnish with lemon wedges and parsley. What to drink: A Chardonnay would be delicious with the haroseth and the salmon and whitefish cakes. We like the apple, pear, and vanilla notes of the Baron Herzog 2006 Chardonnay from Herzog Wine Cellars on California's Central Coast. It's a great kosher wine and a good value at $13.