2.Half-fill large shallow frying pan with water; bring to a boil. Break eggs into cup, one at a time, then slide into pan. When all eggs are in pan, allow water to return to a boil. Cover pan, turn off heat; stand about 4 minutes or until a light film sets over egg yolks. Remove eggs, one at a time, using slotted spoon; place spoon on absorbent-paper-lined saucer briefly to blot up any poaching liquid.
3.Meanwhile, cook prosciutto, in single layer, under preheated grill.
4.Boil, steam or microwave spinach until just wilted; drain. Using hand, squeeze excess water from spinach.
5.Meanwhile, trim end from bread; cut into four slices. Toast bread both sides; divide among serving plates. Top each with 1 slice prosciutto, a quarter of the spinach and an egg, then top with second slice prosciutto.