Wash 250 g potatoes and cook in boiling water for about 20 minutes. Wash parsley, shake dry, cut leaves from the stems and chop finely. Mix flour and baking powder. Peel, wash and finely grate the remaining potatoes. Rinse jacket potatoes cold, peel and grate or mash them finely.
Mix flour mixture, buttermilk, potatoes, parsley, except for a little bit for sprinkling, and 1 egg. Season with 1 teaspoon salt and a pinch of nutmeg. Let it swell for about 10 minutes. Heat butter in portions in a large pan and fry pancakes (approx. 2 tbsp. dough each) in it in portions at medium heat. Keep ready pancakes warm.
Break 4 eggs into cups. Place them one after the other in a wide pot of boiling salt water. Use a fork to place the egg whites around the yolks. Cook for about 2 minutes, remove with a skimmer and drain. Arrange pancakes and eggs and sprinkle with the remaining parsley.