Krkonoše Kyselo Sourdough Soup with Mushrooms

Start the Krkonoše kyselo with its rye starter. In a bowl, whisk the rye flour into lukewarm water until you get a smooth, thin batter with no lumps. Cover the bowl with a kitchen towel and let it ripen in a warm spot until the starter bubbles and smells pleasantly sour, like bread. A shelf near the stove or another warm spot in the kitchen works best.

Add the dried mushrooms to a pot of water, add the caraway seeds and salt and bring to a boil. Simmer for about 10 minutes so the mushrooms release their flavor into the broth. For a stronger mushroom taste, crush the mushrooms into smaller pieces before cooking.

Add the diced potatoes and cook until tender. Then pour the starter through a sieve into the soup and let it gently bubble for about 10 more minutes, stirring, until it thickens. Taste it, the soup should be pleasantly sour. Add salt if needed and watch the consistency, it should be neither watery nor thick like porridge.

Finely chop the onion and sauté it in butter until golden. Crack the eggs in and stir them into soft scrambled eggs.

Divide the scrambled eggs among bowls and pour the hot kyselo over them. Sprinkle with chopped chives and serve right away.