
Shiitake & Carmelized Onion Soup
This past week was less than spectacular in my humble kitchen. I created a weird tofu and bean thread noodle dish with a red wine-based sauce; hmm, it was just OK – I’m guessing no one wants purple tofu :-). My other effort was a repeat: Pepper Steak, but this time I also made beef stock as a side-effect, owing to the fact that I had a lot of left over beef trimmings.
But, it’s a new week, so, today I’m doing something new (to me): a puréed vegetable soup!
My inspiration for this soup was the puréed shiitake mushroom soup at a local restaurant. However, I didn’t have enough shiitake on hand, so I decided to mix it with onion, carmelized for sweetness to balance the earthy, but often slightly bitter, shiitake.

Shiitake & Carmelized Onion Soup Ingredients
Ingredients (yields 6 cups):
- olive oil (~3 T.)
- shiitake mushrooms (~2 oz., dried)
- onion (e.g., yellow or other; I used 2 medium plus 3 small, cut lengthwise in strips)
- soup stock (4 cups, I used homemade beef stock from trimmings boiled with mushroom stems, bay leaves, oregano, rosemary; fat separated)
- garlic (4 cloves)
- fresh ginger (1 thumb, minced, I used half of that shown in the photo)
- salt (~2 t.)
- ground pepper (~3/4 t.)
To prepare, first, reconstitute the dried mushrooms in a bowl of warm water. I placed a small plate over them to keep them submersed; this will take about an hour.

Rehydrating Dried Shiitake Mushroom
Simultaneously, carmelize the sliced onion with 2 T. olive oil in a large pan or pot (8+ cup capacity; I used a 12-inch cast iron skillet) over low to medium-low heat, strirring often, for 45 minutes to an hour. Be careful not to burn the onions, but rather make them tender and browned slowly, adding a bit more olive oil if it seems they are drying out.

Beginning to carmelize the onions and roast the garlic.
In the same pan, roast the garlic cloves until tender and the ginger a bit. Since my garlic cloves were already peeled, I wrapped them in foil as well as the minced ginger, so that it could be easily removed when tender.
When carmelized sufficently, the onions should be moist, browned, and very tender; the garlic cloves should be tender as well. (I removed the garlic from the foil to accelerate the roasting.)

Carmelized Onion and Roasted Garlic
Next, place the rehydrated mushrooms in a colander and press out most of the absorbed water (to avoid excess water in the soup).

Rehydrated and pressed Shiitake Mushroom; save the water!
Coarsely chop the mushrooms and add them, along with the minced roasted garlic, and 2 cups soup stock to the pan with the carmelized onions and bring to a boil, cook for a short time (it seems to me that mushrooms, from dried, should be cooked), then remove from heat.

Carmelized Onion, Chopped Shiitake, Minced Roasted Garlic, and 2 cups stock.
Next, purée the ingredients into a soup, adding the minced ginger, ground pepper, salt, and about 2 cups more soup stock, which you can add progressively to acheive your desired consistency; you can use some of the water used to rehydrate the mushrooms, but be aware that it will impart a bit more bitterness to the flavor.
As with most soups, the right amount of salt is key. Be sure to be conservative and taste test it as you add the salt.
I puréed the soup, somewhat inconveniently, in a traditional blender by adding some soup ingredients and stock little by little, progressively working up to its “liquify” setting. Alternatively, you could purée the soup right in the pan or pot by using an immersion blender.
I served the soup topped with sourdough croutons, simply cubed fresh sourdough bread, pan fried in a little salted butter, and some finely sliced green onion, that was luckily growing out the top of one of my yellow onions that had been left in the sunlight on the countertop for too long. :-)

Shiitake & Carmelized Onion Soup
The result: delicious! It’s got a creamy texture, but without dairy ingredients, and a nice blend of shiitake and sweet onion flavors, and just enough spice to keep you awake, from the ground pepper and ginger.
Alas, the way I prepared it isn’t vegetarian, but it could be done quite easily, of course. Also, I used less than $2 of dried shiitake and onions as well, so it’s a nice, inexpensive, healthy soup!
Here are some related recipes that I considered: