To make the hollandaise sauce, place the egg yolks, lemon juice, salt and pepper in the bowl of a food processor and process until combined. With the motor running, gradually pour the butter in a thin stream and process until thickened. Set aside.
Heat a deep frying pan of water over low heat until just simmering and add the vinegar. Crack an egg into a small bowl and gently pour into the pan. Cook the egg for 2−3 minutes for soft poached or until cooked to your liking. Remove with a slotted spoon and drain on absorbent paper. Repeat with the remaining eggs. To serve, top the bread with the rocket and poached eggs and spoon over the hollandaise sauce. Serves 4.