I thought “everyone” had long breakfasts no matter what part of the blog reading world you were from. And that perhaps what was different would be what was on the table. So I am surprised by your surprise on how different it is. It makes me want to ask you: How is a Sunday breakfast at your place?
Soak the herring filets in water for 1-2 hours, cut them in 1.5 cm strips.
Slice the onion into thin rings or half rings.
In a pan mix the vinegar, sugar, water, and spices heat the pan gently but do not
let it boil, and stir until the sugar has dissolved. Let it cool off.
In a jar layer the sliced herring and onion and pour the cold vinegar marinade.
You can also find a more spiced up recipe here