Rinse the yellow peas thoroughly and soak them in cold water for 10 to 12 hours (overnight). Drain the water and rinse the peas before cooking.
Place the peas, the whole piece of pork, and the whole, peeled onion into a large pot with 1.5 litres of fresh water.
Bring to a boil and simmer slowly for 60 – 90 minutes, until the peas are completely soft and start to break down. Skim off any foam.
Remove the meat and onion. Dice the meat into small cubes and return it to the soup. Discard the onion.
Stir the marjoram into the soup. Season with salt and pepper to taste.
In a bowl, mix the flour and salt. Gradually add the milk while whisking to prevent lumps.
Whisk in the eggs and melted butter.
Cover the batter and let it rest at room temperature or in the refrigerator for at least 30 minutes (while the soup is cooking).
Heat a little butter/oil in a medium frying pan (20-22 cm).
Ladle a small amount of batter (approx. 1/2 dcl) onto the pan. Quickly tilt the pan so the batter spreads into a thin layer.
Fry for about 1-2 minutes on each side until golden brown. Repeat until all batter is used.
First, serve the hot Ärtsoppa with bread and mustard.
Immediately after the soup, serve the freshly fried Pannkakor, folded into quarters, with a spoonful of jam and fresh whipped cream.