Enough Mayonnaise to coat everything, but not mask the flavours
Boil the potatoes in salted water until tender, drain and leave to cool a little.
Meanwhile, boil the eggs to hard boiled then plunge into cold water.
Chop the gherkins, spring onions, potatoes and eggs and place in a large serving bowl.
Mix in the mayo, taste to check seasoning adjusting by adding more gherkins/spring onions/mayo if you want. Can be made ahead of time and kept covered in the fridge until needed. Can also be served warm.