Fish in Beer

	Thoroughly rinse the fish, remove scales, and cut off the heads. Make a careful incision along the belly and remove the innards. Rinse the fish again under running water. Make a small cut near the tail, holding the knife almost parallel to the table surface, and gently separate one fillet. Remove the backbone and rib bones, freeing the second part of the fillet. Repeat the process with the remaining fish.
	In a small pot, pour in 1 liter of water, add thoroughly washed parsley, vinegar, salt, sugar, and peppercorns. Set on high heat and bring to a boil. After boiling, remove from heat and let cool slightly. Roll the fish fillets into rolls, secure with wooden toothpicks, place in a bowl, pour with warm marinade, cover with film, and leave for a day in a cool place.
	The next day, prepare the beer sauce. Peel and chop the onion. Pour the beer into a pot, add the onion, set to medium heat, and cook until the onion is completely dissolved, about 20 minutes. For this recipe, it's best to use only light beers.
	Whip the sour cream using a mixer, add the beer and onion sauce, then season with salt and pepper to taste, and mix well.
	Wash the green onions, dry them with paper towels, and chop finely. Remove the fish from the marinade and transfer it to a strainer. Leave it over a bowl or pot for 10-15 minutes so that all the liquid drains. Arrange the fish rolls on a serving dish, sprinkle with chopped green onions, and drizzle with the beer sauce.