Żurek for Easter - how to make "zakwas"

Instant soup - can be purchased online

If you ever wondered what's a typical Easter soup in Poland, the answer is: "Żurek" or "Barszcz biały".
Both soups are white and sour, served with white sausage and hard boiled egg.
Both are made of sour base - "zakwas" that is achieved by fermenting flour.
While "Żurek" is made of rye flour, "Barszcz biały" is made of wheat flour.
The fermenting process takes between three to five days, so it needs to be planned in advance.
After reading a recipe, I'm more convinced to give it a try. It seems really easy.

"Zakwas":
1 lb rye flour,
6 cups water,
1-3 garlic cloves,
slice of rye bread (optional).

Boil water and mix some of it with flour until loose batter forms. Let it cool. Stir in remaining lukewarm water, add garlic and slice of bread. Set aside for three days. Pour into air tight jars/bottles and store in a fridge up to 2 weeks. "Zakwas" should have clear color.

When this part is done (and remember that it takes at least three days), "Żurek" is made by combining vegetable or meat broth with some of the sour base (approximately 4.5 cups of broth and 2 cups of sour base). You can add some vegetables, such as carrots, celery root and parsley root (white part of celery and white part of parsley), chopped & fried onions, garlic, bay leaf, salt, pepper and marjoram.
Add fried slices of white sausage, hard boiled egg and enjoy!

And if this seems too much, use an instant version! :) I can't complain about this option... :))