I found two frosty packages in the back of the freezer the other day: matsutake buttons, four of them. According to the labels, I had picked them in October, 2010. Two years in the deep freeze!

The matsi were individually wrapped in foil. One pair was sealed in a Ziploc, the other pair vacuum-sealed. With an open bottle of sake in the fridge, I knew immediately the culinary experiment I was about to perform—Matsutake Sukiyaki.

I sort of remember my thinking at the time, two years ago. I had read somewhere that you could freeze firm matsutake buttons, that this was preferable to drying. Maybe someone at Puget Sound Mycological Society had recommended the technique. I had made similar experiments with porcini buttons years earlier. For whatever reason, wrapping the matsi buttons in foil was a required step. It seemed to me the best way to defrost them would be directly in the soup broth. I unwrapped the foil to find, luckily, that I had carefully cleaned the buttons and trimmed the stems before freezing. They looked a little darker but otherwise in good condition. I could smell the signature “autumn aroma” even in their cryogenic state.

And the result? The thawed mushrooms definitely imparted their essence of “red hots and dirty socks” to the soup—not as much as fresh specimens, but more than dried matsutake. The main problem was that the mushrooms were prohibitively chewy. After thawing in the soup, I removed and sliced them; next time I will either slice the thawed matsi razor-thin or cut into bite-sized pieces. As it was, I only ate the smaller slices. The main benefit to the sukiyaki was flavor rather than texture.

My experiments are not over. I still need to test the vacuum-sealed pair of buttons, and next time I’ll try not to lose them in the freezer for more than a few months. Overall, I’d say the results are encouraging for matsutake fans who want to experience the mushroom’s unique taste year-round.