Mackerel can sandwich

Slice the onions at right angles to the fibers and soak them in water for a few minutes, then drain well.

Mix well with butter and mustard that have been returned to room temperature and spread generously on the surface of the bread.

Sprinkle with butter, pour an appropriate amount of mayonnaise, and then add salad vegetables.

Place the loosened can of boiled mackerel and soaked onions on three out of six slices of bread.

Layer it on the bread that you have not placed on the can of the mackerel, cover it with soaking and lightly press it down with your hands, and allow it to blend for a few minutes.

Remove the soak and cut it into bite-sized pieces and you're done.

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- Onion
- 1/3
-
- Unsalted butter
- 60g
-
- mustard
- 1 tablespoon
-
- Sandwich bread
- 6 sheets
-
- mayonnaise
- Appropriate amount
-
- Salad vegetables
- 6 sheets
-
- Can of boiled mackerel
- 1 can