A layer of smoked salmon blankets a square of pumpernickel, and chopped hard-cooked eggs and capers anchor one corner. A sliver of lemon peel marks the middle.
Place eggs in a small saucepan, and cover with water by 1 inch. Bring water to a boil; cover, and immediately turn off heat. Let stand 10 minutes. Remove eggs from pan, and rinse under cold water to stop cooking. Peel eggs, and finely chop. Place in a small bowl. Add capers, and season with salt and pepper; set aside.
Using a vegetable peeler or sharp paring knife, shave lemon zest in long pieces. Finely slice each piece into strips, about 2 3/4 inches long. Cover with a damp paper towel; set aside.
Using a small offset spatula, spread 2 teaspoons lemon mayonnaise on each bread slice. Cover each with a piece of salmon. Using a 2-inch-square cookie cutter or serrated knife, cut out one square from each slice. Place the straight edge of a large knife along the diagonal of each as a guide; spread 1 teaspoon egg mixture over the exposed half. Remove knife, and place a lemon strip along the edge of the egg mixture so that it is resting on the diagonal.
Gently separate outer leaves of remaining whole capers until they resemble flowers; place on salmon in the half not covered with egg mixture. Serve.