In a large pot, add about 1 inch of water and steamer insert. Poke a few holes in the sides of each potato (don't peal them) then add to the steamer basket. Bring the water to a boil and add the lid to the top of your pot. Steam for 15-20 minutes until potatoes are soft and tender. While potatoes are steaming move onto veggie prep.
Use a mandoline set to cut at ¼ of an inch thick. Carefully run the cucumber, peeled carrot and white onion over and slice into even pieces.
Add the sliced onion and cucumber to a medium sized prep bowl and sprinkle a generous amount of salt over and toss to combine. Let rest to sweat and release excess moisture.
Slice large pieces of carrots in half with a pairing knife. I like to do this so all the vegetable are about the same size, but you can leave them whole if you wish. Optional: Add the sliced carrots over top of the potatoes for the last couple minutes of cooking. This will soften the carrots and make them have less of a crisp texture. Totally optional and you can leave your carrots raw or cook them.
Once the veggies have release a good amount of liquid (you should see them sweating) take a a handful at a time and squeeze to release even more liquid. Set the squeezed veggies on a paper towel until ready to add to the salad.
Once the potatoes are soft and finished steaming, remove the skin and add to a large prep bowl. Let the potatoes cool before adding the rest of the ingredients.
Remove shell from boiled eggs and add into the bowl with the potatoes. Mash/stir until the egg is well incorporated. Next, add in the mayonnaise, sea salt to taste (white pepper optional), and rice vinegar and stir to combine.
Finally add in the prepped veggies and gently stir until just incorporated. Let sit in the fridge until ready to serve cool. I like to add additional boiled eggs over the top of my potato salad when serving, but this is optional. Enjoy!
Leftover Storage: Store leftover potato salad in the fridge for up to 3 days. Serve cool.Veggie Tip: Give the sliced cucumbers and onion a good sprinkle of salt and let them sit for a bit. This helps the veggies release excess moisture. Once they sit give them a good squeeze to release even more liquid. This will help your potato salad not be watery.Potato Tips: I recommend steaming or roasting the potatoes instead of boiling them. When boiled the potatoes with hold a lot more liquid and could turn your Potato Salad watery when letting it sit in the fridge. If you do boil the potatoes, leave the skin on and remove it after. This will help reduce the amount of moisture they hold.Make Ahead: You can make this Potato Salad up to 24 hours ahead of time and store in the fridge until ready to serve.