Japanese Egg Sandwich (Tamago Sando)

Ingredients

Ingredient notes & substitutions

Eggs:

6 large eggs boiled 7 minutes give you jammy, medium-set yolks that make the egg salad extra creamy — go 10 minutes if you want fully hard-boiled for a lunchbox.

Kewpie mayo:

This Japanese mayo is made with only egg yolks and rice vinegar, giving it a richer, tangier flavor than American mayo — find it in the Asian aisle or online, and it's worth seeking out.

Japanese milk bread (shokupan):

Its soft, slightly sweet crumb is what makes this sandwich iconic — look for it at Asian grocery stores or a well-stocked bakery, and use thick-cut slices if you can.

Unsalted butter:

Softened butter spread edge-to-edge on both bread slices seals out moisture, which is the real secret to keeping the sandwich from turning soggy.

Sugar:

Just a pinch balances the richness of the mayo and eggs — it's a classic touch in Japanese egg salad, so don't skip it even though it seems small.

Milk:

Only needed if you go the hard-boiled route — a splash loosens the drier yolks back into a creamy, spreadable texture.

Method

1. 1

   Prepare an ice bath in a large bowl.

2. 2

   Bring a pot of water to a boil, then gently lower in the eggs. Boil 7 minutes, turn off the heat and let sit 1 minute for jammy medium eggs (or boil 10 minutes for hard-boiled). Transfer to the ice bath for 2 minutes, then peel while still lukewarm.

3. 3

   Add the peeled eggs to a bowl and mash with a fork, then season with the sugar, salt and pepper. Keep mashing to pieces smaller than a pea but bigger than minced (a paring knife helps).

   
4. 4

   Stir in the Kewpie mayo (and the milk, if you used hard-boiled eggs) until creamy. Taste and adjust salt, pepper or mayo.

5. 5

   Spread 1/2 tablespoon softened butter evenly onto each slice of milk bread — this seals the bread so it doesn't go soggy.

6. 6

   Pile the egg salad generously onto one slice, top with another slice buttered-side down, and press gently.

   
7. 7

   Slice the crusts off all four sides, then cut each sandwich in half (or into thirds/triangles). Garnish with chives and serve, or wrap for later.

   

Variations to try

• Swap in furikake or a pinch of togarashi mixed into the egg salad for a savory, umami kick.
• Add a thin layer of thinly sliced cucumber or a few leaves of shiso between the bread and egg salad for crunch and freshness.
• No Kewpie on hand? Use regular mayo plus 1/4 teaspoon rice vinegar and a tiny pinch of sugar to mimic the tang.
• Make it dairy-free by skipping the butter and lightly toasting the bread instead, or using a plant-based butter substitute.

Storage & make-ahead

The egg salad can be made up to 2 days ahead and kept covered in the fridge — just give it a stir before spreading. Assembled sandwiches keep well wrapped tightly in plastic wrap for up to 24 hours in the fridge, which is what makes them great for lunchboxes; use fully hard-boiled eggs if you're packing them ahead, since jammy yolks are best eaten the day they're made. This sandwich doesn't freeze well, as the egg salad and soft bread both lose their texture once thawed.

Frequently asked questions

Can I use regular mayonnaise instead of Kewpie?

Yes, regular mayo works fine — just stir in a tiny splash of rice vinegar and a pinch of sugar to get closer to Kewpie's tangier, richer flavor.

Why do I need to butter both slices of bread?

Butter creates a moisture barrier so the egg salad doesn't soak into the bread, which is especially important if you're making the sandwich ahead or packing it for lunch.

How jammy should the eggs be?

For the classic convenience-store texture, boil 7 minutes for a soft, just-set yolk that mashes into a creamy salad; if you prefer no runniness at all (or you're packing it for later), boil the full 10 minutes.

Where do I find Japanese milk bread?

Look for shokupan at Asian grocery stores, some Asian bakeries, or online — if you can't find it, a soft white sandwich bread or brioche loaf is the closest substitute, though the texture won't be quite as pillowy.