Cook potatoes: Scrub the potatoes; you can peel them if you wish (See Note 1). Cut them into larger chunks. Place them in the pot, cover them with cold water, and bring to a boil. Add salt and sugar and cook the potatoes until fork-tender but not falling apart; it will take 10-15 minutes once the water starts to boil. Drain them well and place them into a large bowl.2 lbs potatoes + 1 teaspoon fine sea salt + 1 teaspoon granulated sugar
Prepare ingredients: In the meantime, prepare the other ingredients and make the dressing.
Chop salad ingredients: Drain the tuna. Finely chop the green, red onions, and parsley. Roughly chop the capers. Set them aside, but don’t place them yet into the salad bowl.1 can of tuna + 2 green onions + 1 small red onion + a small bunch of parsley + 2 teaspoons capers
Dressing: In a small bowl, mix the grated garlic cloves, vinegar, mustard, sugar, salt, and pepper. Add the olive oil and whisk until the dressing emulsifies slightly.5 tablespoons olive oil + 2 garlic cloves + 2 tablespoons apple cider vinegar + 1 teaspoon whole grain mustard + 1 teaspoon Dijon mustard + ½ teaspoon granulated sugar + ½ teaspoon fine sea salt + ¼ teaspoon ground black pepper
Finish salad: Pour ½ of the dressing over the warm potatoes in the bowl. Toss gently to coat them, but be careful not to crush them. Add the remaining ingredients and dressing, and toss again. Adjust the taste with salt, pepper, and maybe a bit of extra vinegar if desired.
Notes
Potatoes: I used small, red-skinned salad potatoes, which are a waxy sort. You can also use Yukon Gold, fingerling, new potatoes, and white potatoes. Red-skinned potatoes usually have a thin skin, and I don’t peel them. I also don’t peel fingerling and new potatoes. If you use potatoes with thicker skin, it’s preferable to peel them.
Tuna in oil: Drain it well to remove the excess oil. If you like, you can use 1-2 tablespoons of the can oil to replace some of the olive oil.