Hard-boil the eggs for roughly around 8 minutes and rinse them in cold water once cooked.
Peel the eggs and place them into a bowl. Take a knife and chop up the eggs to a fine consistency; this will help the egg stay in the sandwich and not escape all over your lap!
Stir in your Rich Yolk mayonnaise and season to taste.
Lightly butter your bread; spread the egg mixture evenly over half of the slices of bread. Top with peppery watercress and the remaining bread slices.
Take your sandwiches, remove the crusts and slice into fingers or diagonally to form 4 triangles – we all have our own preferences!