Boil potatoes in well-salted water until tender, about 20 minutes, or until you can poke them easily with a fork. Drain, and let cool, just enough so you can handle them. Cut them in half lengthwise.
Preheat oven to 450°F.
In a bowl, add paprika or chili powder, then add the olive oil, stir to combine, then add the potatoes and toss until coated.
On a sheet tray, arrange potatoes cut side down, and bake for 30 minutes, or until crispy and golden brown. Remove tray and flip potatoes over to let cool.
Once cool enough to touch, top with one piece of pickled herring, a small slice of onion, and a sprig of dill. Flake salt to finish.