Tunnbrödsrulle are a popular Swedish street food made of a tunnbröd, or flatbread, topped with a layer of mashed potatoes, two hotdogs, Skagenröra (shrimp salad), fried onions, ketchup and mustard.
Melt the butter in a frying pan and chop onion into thin slices. Add onion to the butter and cook on low heat for about 15 minutes, until golden caramel.
Cook hotdogs however you prefer (eg. boil water and take off heat and let hot dogs cook in the hot water for about 10 minutes).
Set lomper on two plates. Add about 4 tbsp of mashed potatoes to each lompe. Sprinkle with fresh parsley.
Add two hotdogs on top of the mashed potatoes on each lompe.
Add 3 tbsp of Skagenröra per plate on top of the hotdogs.
Top with fried onions, ketchup, and/or mustard. Roll up the lomper and enjoy!