This recipe calls for your creativity.  The example is just that – you can copy or use as an example.  Start with a base of lettuce leaves, any type you desire.  If you use leaf lettuce, spread the leaves out flat to make a base.  Upon that layer your desired salad toppings.  Hard-boiled eggs are always on the traditional Dutch dish.  Cold peas, sliced olives, lentils, etc.  If serving as a main course, canned albacore tuna is often used or rolled meats.  Feta or Blue cheese can be used in place of the mozzarella balls.  The goal is a shallow layered salad that is served on a platter.  Drizzle with a light olive oil/vinegar blend or serve on the side.