Japanese Potato Salad Bagel with Quick-Pickled Cucumber

Japanese potato salad has always felt like a dish that knows something you don’t. It looks familiar enough to lull you into confidence, then quietly refuses to behave the way you expect.

Often called potesara, Japanese potato salad is a comfort food staple, found in home kitchens, bakeries, convenience stores, and izakayas, where it’s less a side dish than a soft place to land. The idea arrived long ago as part of Japan’s early flirtation with Western cooking, but what stuck was something quieter and more specific: potatoes mashed while still hot, dressed generously, smoothed out with mayonnaise, and studded with vegetables that feel fresh rather than sharp. Somewhere along the way, it stopped being an adaptation and became its own thing.

This version starts with russet potatoes, peeled, boiled, and mashed just enough to leave some texture behind. While they’re still warm, they’re folded with Kewpie mayonnaise, rice vinegar, salt, pepper, a little karashi mustard for heat, chopped hard-boiled egg, and thin slices of Persian cucumber and carrot. It’s rich, but not heavy. Creamy, but not flat. The kind of salad that tastes finished without needing improvement.

Then it becomes a sandwich.

A plain bagel gets toasted and buttered, because if you’re going to do this, you might as well commit. One half is layered with quick-pickled cucumbers. They can sit for an hour, or overnight if you remember, becoming lightly sweet, gently acidic, and very good at cutting through creaminess. The potato salad is piled on top, unapologetically, and the bagel goes back on like it knows its job.

This is good food for watching Wakakozake. It’s a short, gentle anime about a woman who eats and drinks alone after work, visiting small restaurants and taking real pleasure in simple food done well. Episodes are only a couple of minutes long. Nothing explodes. No one yells. She takes a bite, pauses, and exhales: pshuu. That sound is important. It’s the sound of something hitting exactly where it should.

Nothing here is trying to be clever. It’s a soft, indulgent, slightly unruly sandwich that understands its job. It doesn’t need to be a meal and a statement. It just needs to be good, eaten slowly, preferably while watching someone else enjoy their dinner in silence.

The Recipe

Makes enough egg salad for 4 bagel sandwiches.

Ingredients

For the Japanese potato salad

• 2 lbs russet potatoes (about 3–4 medium), peeled

• ½ cup Kewpie mayonnaise

• 1–2 tablespoons rice vinegar

• 1 teaspoon karashi mustard (or any spicy mustard), to taste

• Salt

• Black pepper

• 2 Persian cucumbers, thinly sliced

• 1 medium carrot, shaved into ribbons

• 2 scallions, sliced

• 2 hard-boiled eggs, chopped

For the quick-pickled cucumbers

• 2 Persian cucumbers, thinly sliced

• ½ teaspoon salt

• 1–2 teaspoons honey

• ¼ cup apple cider vinegar

• 1 small clove garlic, lightly crushed

• ½ cup water

Directions

1. Cook the potatoes.
   Cut the potatoes into large chunks and place them in a pot of cold, well-salted water. Bring to a boil and cook until very tender, soft enough that a knife slides through without resistance. Drain well.

2. Mash while hot.
   While the potatoes are still steaming, mash them gently in a large bowl. You’re not going for smooth, leave some texture. This is important.

3. Season the base.
   Add the Kewpie mayonnaise, rice vinegar, mustard, salt, and black pepper. Fold gently until creamy and cohesive. Taste and adjust seasoning while everything is still warm.

4. Add the mix-ins.
   Fold in the sliced cucumber, carrot ribbons, sliced scallion, and chopped hard-boiled eggs. The vegetables should soften slightly from the warmth without disappearing. Chill until cool, at least 30 minutes, before serving or sandwiching.

Quick-pickled cucumbers

Combine the sliced cucumbers, salt, honey, apple cider vinegar, garlic, and water in a jar or container. Shake or stir to dissolve the salt and honey. Let sit at room temperature for at least 30 minutes, or refrigerate for a few hours (or overnight) for deeper flavor.

Serve

Serve chilled, piled generously onto toasted bread or a buttered bagel, with the quick-pickled cucumbers layered underneath or scattered on top.

Note

If the potato salad runs out before the pickles do (which happens), keep going anyway. The quick-pickled cucumbers on a warm, buttered bagel are quietly excellent on their own, salty, sweet, sharp, and a little indulgent.