Prep the ingredients per the instructions above.
Rinse the herring filets under cold water and pat them dry with a paper towel.
Slice the bread rolls in half and lightly toast in a toaster oven or oven broiler on low.
In a small bowl, mix together the mayonnaise and Dijon mustard. Season with salt and pepper to taste.
Spread the mayonnaise and mustard mixture on the bottom halves of the bread rolls.
Place a herring filet on each roll and top with sliced onions and pickles.
Sprinkle fresh parsley and chives over the toppings.
Place the top halves of the bread rolls on the sandwiches to complete the broodje haring.
Mix the ingredients for the lemonade.
Serve the sandwich with potato chips and lemonade.