The Fact of Freezing Fungi

Dear Tamar:

What is a good use for a bag of frozen chopped mushrooms?

-Freezing Fun Guy

Dear Freezing Fun Guy,

The entry on mushrooms in Waverley Root’s Food: An Informal Dictionary quotes this warning from the 1526 Grete Herball :

“They that be not deedly [deadly] have a grosse gleymy [slimy] moysture that is dysobedyent to nature and dygestyon, and be peryllous and dredful to eate & therefor it is good to eschew them.”

This isn’t really relevant except that I needed “grosse gleymy” for my reply. Whether or not you agree with the Grete Herball about all mushrooms, your chopped frozen ones will be grosse and gleymy within minutes of exiting the freezer for use, and what you’re asking is whether anything can tack hard enough to go from that to edible.

The cause of your gleym is water. Mushrooms are mostly water. They are so watery that culinary schools used to say not to wash them—avoiding more water. (This is silly. The tiny amount they absorb evaporates with the rest. Wash away.) When you freeze mushrooms, you are making mushroom-shaped ice cubes. When they thaw, they become liquid with a fungal manner. We are looking for dishes that will accommodate the fallout.

This is doable. It’s just a matter of finding dishes where: a) the mushrooms are finely chopped, so their gleyminess isn’t very noticeable and b) they are bound in liquid, so their leaking isn’t a flaw but an attribute.

The one that springs first to mind is a mushroom sauce I tasted my senior year of college. It was made by Elizabeth Adams Ames, the only person I’ve ever met who was great at everything she did. (This extended to strange, esoteric things—during our Junior year abroad in Barcelona she coached the Barca youth ice hockey team.) One night, senior year, she materialized with bowls of linguine—already sophisticated—sauced with a glossy mushroom sauce, unique for having no cream in it, and thus tasting deeply, essentially of mushroom. I was young and new enough that something like really mushroomy mushroom sauce was a revelation. I believe the sauce was the Mushroom Gravy from a Mollie Katzen cookbook.

What makes it a particularly good fit is that it’s thickened with cornstarch. I’m adapting the recipe below, keeping your unique circumstances in mind. But remember the credit goes to Mollie Katzen and the maddeningly talented Elizabeth Ames.

Linguine with mushroom sauce, heavily adapted from Mollie Katzen

• Olive oil

• 1/2 onion, finely diced (1/2 cup)

• 1 tsp fresh thyme, chopped

• 1/2 tsp salt plus to taste

• 1 clove garlic, finely chopped

• Bag of frozen mushrooms, thawed in a colander over a bowl, liquid kept, very finely minced

• 2 tbsp salted butter

• 2 tbsp sherry

• 2 tbsp cornstarch

• 3 cups stock—mostly chicken or vegetable, some can be mushroom liquid

• 1 lb linguine

• Parmesan cheese, freshly grated (Optional)

• Chopped parsley (Optional)

Heat a heavy bottomed pan large enough to hold the pasta. Add 2-3 tbsp olive oil, then the onion, thyme, and salt. Cook over medium heat, stirring occasionally, until the onion begins to soften. Add the garlic and continue cooking until the onion and garlic can be easily smashed. Add the mushrooms and butter and cook over medium-high heat, stirring, until the liquid is almost entirely gone, 10-15 minutes. Meanwhile, whisk the cornstarch into 1 cup of broth.

Bring a pot of water to boil. Salt the boiling water to taste like pleasant seawater, and cook the pasta to al dente.

Add sherry to the mushrooms. Cook until the alcohol evaporates, and you can no longer smell it. Add the remaining broth to the pan. Bring to a boil, then lower to a simmer. Slowly drizzle in the cornstarch slurry. Taste for salt and adjust.

When the pasta is just cooked, add to the sauce, stir through, and add a drizzle of olive oil if desired. Serve topped with freshly grated parmesan, topped with chopped parsley, if you like.

My second idea also leans into soupiness. It’s a very 1990s mushroom soup with thyme and sage, pureed to smooth and creamy—again obviating the texture and embracing soupiness. My quantities below only make a little soup, because I didn’t want to tell you to get more mushrooms. If you want more soup, get more mushrooms.

Creamy mushroom soup

• Olive oil

• 2 tbsp salted butter

• 1/2 onion, finely diced (1/2 cup)

• 1/2 tsp salt plus to taste

• 2 cloves garlic, finely chopped

• Bag of frozen mushrooms, thawed in a colander over a bowl, liquid kept, very finely minced

• 1/4 cup sherry

• 1 tablespoons flour

• 1 cup cream

• 2 cups stock—mostly chicken or vegetable, some can be mushroom liquid

• 1 bay leaf

• 1 sprig thyme

• Chopped parsley (Optional)

Heat a soup pot. Melt the butter in 2-3 tbsp olive oil, then add the onion and salt. Cook over medium heat, stirring occasionally, until the onion begins to soften. Add the garlic and continue cooking until the onion and garlic can be easily smashed. Add the mushrooms cook over medium-high heat, stirring, until the liquid is almost entirely gone, 10-15 minutes. Add sherry to the mushrooms. Cook until the alcohol evaporates, and you can no longer smell it. Sprinkle in the flour, stirring through until it’s absorbed. Slowly add the liquid and the herbs. Bring to a boil, then lower to a simmer and cook to combine, another 10-15 minutes. Taste for salt and adjust. Remove the bay leaf and thyme. Puree until completely smooth—in a standing blender or with an immersion blender. Serve warm, topped with chopped parsley if you like.

Dear cook, I don’t know why they froze your fungi, but if these recipes are too good and you’re tempted to do it again…Don’t. If you feel compelled to have frozen mushrooms on hand, cook them simply first in olive oil until their moisture has evaporated. Then submit them to the requisite chill. It will result in less grosse gleym.