Peel the potatoes, halve or cut into quarters (alternatively boil whole and peel and chop later) and boil in salted water. Try not to overcook them. Drain and set aside to cool. Boil the eggs, drain and rinse under cold water (they'll peel better) then peel and cut them into quarters (once cooled).
While you are waiting for the potatoes to cool prepare the dressing. In a bowl combine all the dressing ingredients, adjust the seasoning as needed and stir until smooth. Refrigerate, covered, until you are ready to make the salad.
In a large bowl combine the potatoes with the eggs, capers and dill, pour in the dressing and stir gently to combine. Adjust the seasoning if needed and chill for 30 minutes before serving, if possible.
Use salad potatoes, such as Charlotte or red, yellow or Yukon Gold.
To save time you can boil the potatoes and eggs ahead and once cooled refrigerate them until you are ready to make the salad. Try not to overcook the potatoes (even salad potatoes can end up a little mushy if cooked for too long).
You can also make the dressing ahead and refrigerate it, covered (for up to 2 days), until you are ready to make the recipe.
I made a moderate amount of the dressing but you can double the ingredients for a creamier salad.
Chill the salad for 30 minutes before serving, if possible. Consume within 3 hours.