Mix Sando (ミックスサンド, mixed Japanese sandwiches)

Ingredients

Equipment Needed

• •Sharp bread knife or thin-bladed hōchō
• •Small pot for boiling eggs
• •Fine-mesh strainer
• •Plastic wrap or a clean kitchen cloth
• •Cutting board

Instructions

1. 1

   Boil the eggs

   Put the eggs in a small pot, cover with water, and bring to a steady boil. Cook for 10 minutes, then cool them in cold water until you can handle them. A fully set yolk gives the filling body; a soft yolk tastes pleasant but makes the bread damp, and damp bread is where a sando loses its manners.

2. 2

   Make egg filling

   Peel the eggs and separate yolks from whites. Mash the yolks with 1 1/2 tablespoons mayonnaise, rice vinegar, half the salt, and white pepper until smooth, then finely chop the whites and fold them in. Mixing the yolks first makes a creamy base, while the chopped whites keep the filling from turning into paste.

3. 3

   Season the tuna

   Press the tuna in a strainer or between paper towels until it feels almost dry, then mix it with 1 tablespoon mayonnaise, soy sauce, and the rinsed onion. The soy gives depth without making it salty, and squeezing the tuna first lets the mayonnaise bind instead of slide.

4. 4

   Dry the vegetables

   Pat the lettuce and cucumber until no water clings to them. If the cucumber is very watery, sprinkle it with a tiny pinch of salt, leave it 5 minutes, then blot again. This is not fussing. Raw vegetables keep giving off water after the sandwich is closed, so you deal with it before the bread has to.

5. 5

   Butter the bread

   Lay out the shokupan slices and spread a very thin layer of softened butter on one side of each. Add karashi to the butter if you like a quiet bite. The butter is not there for richness alone; it makes a small fat barrier, enough to protect the crumb without announcing itself.

6. 6

   Build three sandos

   Make one egg sando with the egg filling spread evenly to the corners. Make one tuna mayo sando the same way, keeping the layer level and modest. Make one ham-lettuce sando with two slices of ham, dried lettuce, and cucumber. Even thickness matters because the cut has to pass cleanly through every corner.

7. 7

   Rest and trim

   Wrap each sandwich snugly in plastic wrap or a clean cloth and rest for 10 minutes with the seam side down. This short rest lets the bread and filling settle into one piece, so trimming does not push everything out the sides. Cut off the crusts with a sharp knife, using a light hand.

8. 8

   Cut triangles

   Wipe the knife clean, then cut each sandwich diagonally into two triangles with one long, gentle pull. Do not saw. A clean cut shows the filling in bright layers and keeps the soft bread from compressing. Arrange one triangle of each kind per serving, with the cut faces turned forward.

Chef Tips

• •Buy shokupan the day you plan to serve it, or the day before at most. This dish asks for softness, not chew. If the loaf feels dry, change the dish and toast it for another use.
• •Japanese mayonnaise matters here because it is thick, egg-rich, and a little tangy. If you use another mayonnaise, add a few drops of rice vinegar and keep the quantity restrained.
• •Drain harder than you think. Tuna, lettuce, and cucumber all carry water, and water is the enemy of the konbini-style clean bite.
• •Cut the crusts after filling, not before. The square shape gives you clean edges while you build, and the final trim makes all three sandos look like they belong together.
• •For meal prep, wrap each finished sando tightly and keep it cold, but serve it the same day. This is picnic food, not a storage project.

Advance Preparation

• •The eggs can be boiled one day ahead and kept refrigerated in their shells.
• •The egg filling and tuna filling can be mixed up to 12 hours ahead, kept separately, and stirred once before spreading.
• •Assemble the sandos no more than 4 hours before serving. Keep them wrapped and chilled, then trim and cut close to serving for the neatest faces.

Frequently Asked Questions

Nutrition Information

1 serving (about 295g)