Ash Reshteh, made with herbs, legumes, and noodles is the most popular & famous "thick soup" across all regions of Iran, especially during winter. It is also one of the main dishes of Norooz (Persian new year - starts 20-21st march). It is very similar to the Italian Minestrone. Very rich and aromatic because of the fresh herbs, turmeric and the 3 very important toppings for Iranian thick soups: Piāz dāgh (fried/caramelized onion), Sir dāgh (fried garlic) & Nanā dāgh (fried mint)!
Ash reshte basicly is a vegan dish but in different regions it serves in a different ways; In some of the regions "Kashk" ( a thick whitish dairy similar to whey or sour cream, and commonly used in traditional Persian & Kurdish cuisine) is added to the whole Ash Reshteh, in other regions it is used as a topping. In other regions vinegar or Torshi (sour pickles) are often used instead of Kashk. In fact, it all depends on your taste and how you like your Ash Reshteh!
In old Persia the word "Ash" had the meaning of "food", or anything with nourishing potential. During the years, though, the word specialized and it is now used to refer to thick soups; made with herbs, vegetables, often with the addition of Reshteh (persian noodle/pasta) or long grain rice. In fact this Ash (thick soup) called "Ash Reshteh" because of the use of Reshteh (Persian noodle/pasta) in it.
Some tips before you started:
Cook your Ash Rehsteh in a large pot.
The heat should always be on high or medium-high heat; cooking the Ash Reshteh on low heat will make it washy and very dark in color.
Stirring and being present while you're making your Ash is the key of this delicious, beautiful, Persian thick soup.
Never cover the pot while cooking Ash Reshte, that will kill the beautiful color of your legumes and herbs, you can add boiled water or broth if needed.
You can find Reshteh (Persian noodle/pasta) in any Persian store in US and UK; otherwise you always can use Linguine Pasta. But remember that Persian noodle is only made with flour, water and lot of salt; in fact if you use it for this recipe, be careful with additional salt. In shape and size they are exactly like Linguine Pasta, but white.
You can also find the dry herbs & Kashk in any Persian store. Otherwise you can replace the dry herbs with the fresh ones. And replace the Kashk with yogurt.
Calamintha nepata is from a mint family and it's the variety it used in Iran and in Persian cuisine.
The herbs should be chopped in the size of basil leaves or even a little bit smaller. Usually for cooking you should remove them and let them dry out on a clean sheet; but in this case, after washing them with cold water, they can be used straight from the colander.
You can also doubled the quantity of toppings by making more of caramelized onion, fried garlic and fried Calamintha nepata. That will make your Ash even tastier —Noghlemey