Ingredients

• 10 ounces skinless salmon fillet, cut into 1-inch pieces
• 3 tablespoons plus 1/2 cup purchased tartar sauce
• 2 tablespoons chopped fresh dill
• 1/4 teaspoon salt
• 1/4 teaspoon ground black pepper
• 1 teaspoon grated lemon peel
• 2 sesame-seed rolls, split
• Red onion slices
• 4 Bibb lettuce leaves

Instructions

1. Place salmon fillets, 3 tablespoons tartar sauce, 1 tablespoon dill, salt, and pepper in processor. Blend using on/off turns until coarsely ground. Form into two 1/2-inch-thick patties. (Can be made 6 hours ahead. Cover and refrigerate.)
2. Prepare barbecue (medium-high heat). Whisk 1/2 cup tartar sauce, 1 tablespoon dill, and lemon peel in medium bowl to blend. Grill rolls until toasted. Transfer to 2 plates and spread bottom halves generously with sauce. Grill patties until fish is cooked through, about 2 minutes per side. Place burgers atop sauce on rolls. Top each with onion slices, 2 lettuce leaves, and top half of roll. Serve, passing remaining sauce separately.