When we think of ‘French soups’, we automatically picture a bowl of caramelized onions, floating in a rich, brown beefy broth, topped with a cheese toast… But what comes second? For me, it’s always Cream of Mushroom!
And I can tell you, there are as many ways to make Cream of Mushroom Soup as there are chefs who make it. But that’s not a bad thing…
A classic approach
The ingredients of a classic thick, rich Creamy Mushroom Soup are essentially chiseled in stone: Fresh mushrooms; heavy cream; onions, garlic and a sprig of thyme; Butter and flour. Depending on whether you want a regular or a veg-etarian-friendly version – chicken or vegetable stock.
You caramelize the fineley-chopped on-ions in the butter, on medium low. It may take as much as 15 minutes. About 3/4 of the way through, add the minced/pressed garlic. You must not rush the process. The longer you simmer the on-ions, the more flavour you get.
Then add the mushrooms – sliced fairly thinly. They’ll cook quickly. I like to boost the temperature to medium high at this stage, to get the mushrooms actually frying, rather than just poaching. This deceptively minor detail is what gets you the absolute most flavour for your mushroom buck!
The pot thickens…
Some cooks add a tablespoon or 2 / 15 – 25 ml of flour at this point. This is to make a roux to help build the thick, rich, velvety base you want for this soup. Stir the flour in all around the pan, until all the dry flour has been completely coated in butter. Let the roux ‘mature’ for a few minutes to ensure that your finished soup is not marred by any hint of raw starch…
Once the mushrooms are just cooked through, and (if you’re lucky) start to get little fringes of toasty-brown goodness around the edges, you can add the stock and the thyme. Put the thyme in whole, on the stem. You’ll want to remove it later. Stir gently but thoroughly to ensure the roux is completely dissolved in the stock. Let the soup come back up to bubbling, then turn the temp back down to ‘simmer’.
The final act…
… Is to add the cream. Even if you don’t use a roux, the heavy cream will create a thick, rich saucy backdrop for the mushrooms. Keep stirring as you add it, so it doesn’t scald.
Let the pot come back up to a gentle bubbling simmer then turn it down to medium low again. Give the soup a good 55 to 20 minutes, stirring occasionally, to mature, meld and marry all the flavours. In the end, you want a mushroom-forward, unified flavour profile featuring the caramelization of the onions, and starring some serious umami notes courtesy of the mushrooms.
My take
Just add some crusty bread – to dip and mop-up with – and you’re good to go!
There are many opinions about what kind of mushrooms you should use to make the ultimate creamy mushroom soup. I prefer Creminis, because they’re full of flavour, readily available where I live (from a local grower), and also relatively inexpensive.
Another major point of debate among mushroom soup aficionados is… To blend? Or not to blend? Some folks prefer to keep the mushroom slices whole for visual character and texture. Others insist you have to run the finished soup through a blender to produce a uniformly fine, creamy texture. That’s entirely up to you!
There’s no need to get fancy or complicated with additions and refinements to this soup. It’s the es-sence of the old rule that simple is inherently elegant. And it’s too easy to drown or blur the subtle, blessed experience afforded by the mushrooms themselves – which is, after all, why you came there in the first place…
~ Maggie J.