Place whole potatoes in medium pot, and cover with water. On high temperature, bring to the boil and turn heat to low. Place lid on potatoes and let cook till soft.
While potatoes are cooking, in a small pot, boil eggs for about 10 minutes, turn off heat and put lid on for 5 minutes. Drain off water and run cold water over eggs to cool down.
In the meantime, slice onion.'
When potatoes are soft, drain off hot water and run cold water over them to cool down. Once potatoes are cooled down, peel if desired. Smash each potato and dice. Place into bowl and allow to cool down fully by placing bowl in refrigerator or freezer (check frequently and give a stir) until slightly chilled .
Peel and dice eggs. Place in fridge to cool down.
Whisk mayo, yogurt, mustard, , relish, until well mixed.
Place potatoes, eggs, and onions in bowl. Stir in mayo mix. Add in salt and pepper to taste.Put in serving bowl and cover top with paprika.