Un Magnolia Pensant: Cooking Houba-zushi with fragrant leaves of Japanese Bigleaf Magnolia ホウバ寿司

Returning to the topic of wrapping foods with leaves (in my previous posts here, here, and here), there was one leaf I thought impossible for me to try. It was of Japanese Bigleaf Magnolia (Magnolia hypoleuca). Bigleaf Magnolia is a common species in large forests of Yokohama, like Niiharu Citizen Forest 新治市民の森. The wood of Magnolia hypoleuca is hard and resilient to water without much resin. Traditionally, Japanese have used it for heels of clogs, hilts of swords and cooking knives, and chopping boards. Actually for chefs of Japanese cuisine, chopping boards made of Bigleaf Magnolia is one of the bests. (Another recommended wood for professional chopping boards is ginkgo – Ginkgo biloba, and rose-gold pussy willow – Salix gracilistyla.) It seems to me using Bigleaf Magnolia for tools is becoming more and more difficult these days due to urbanization … Though, its leaves, called Houba in Japanese, are still used regularly for regional cuisine. Using leaves of magnolia does not require chopping the tree down, right?

One of Japanese Bigleaf Magnolias in Niiharu Citizen Forest

Japanese used Houba as dish for millennia. Houba leaves are not edible, but its chemical component is not poisonous but antiseptic with the scent of magnolia. In 1934 archeologists found Houba on a cup stored in the 6^th century Ouzuka Mound Tomb 王塚古墳, an ancient tomb of some nobles in northern Kyushu 九州. For one thing, the leaf is HUGE and so-so strong. It can be 40cm*20cm easily. It is not torn when we serve food on it. Another merit is its elegant but harmless scent. It’s magnolia so that the entire plant emits sweet soothing aroma. Using Houba for cooking is regional specialty in Gifu Prefecture 岐阜県. When you visit mountainous Takayama City 高山市, or Shirakawagoh Village 白川郷, a menu with Houba is regulars. Wrapping food with the leaf for a while, the smell of magnolia will be transferred to the meal. Or, when we heat miso-paste with chopped veggies on dried Houba over charcoal fire, the miso becomes dip source with gentle flavor. (Recipe is here.) Yep. We can find Bigleaf Magnolia without visiting Gifu. Dried Houba is available from Amazon, for about USD 7 (10 leaves, I tell you). Though, we have the trees (plural!) in Niiharu Citizen Forest 新治市民の森. Why should I pay $7 + shipping fee for that !? … The problem is, they are large trees. I cannot reach to the leaves some 20m above over there.

Another Bigleaf in Niiharu

I almost gave up cooking with Houba. Then, one weekend morning of this June, after continuous days of strong winds and rain, I hit lucky. In Ikebuchi Hiroba Open Space いけぶち広場 of Niiharu Citizen Forest, there is a large Japanese Bigleaf Magnolia, taller than wild cherry blossom trees (Cerasus jamasakura). The open space is the meeting-place for Niiharu Lovers before starting forestry activities. I’ve been there early on that particular morning, and found lots of Houba fell off from the high places. They lay around here and there, without blemish. Yeah, Houba is sturdy enough to be a receptacle for meals, but it cannot stand stamping by visitors, et al. Yet, in that morning, they were still intact. Bingo!

Bigleaf Magnolia in Ikebuchi Hiroba

I collected and brought them home. Washing them under running water, they smelled very sweet. I’ve used some of them to wrap home-made sushi and keep the rest in the freezer for my later treat (ho ho ho 😁). Wrapping sushi with Houba is called Houba-zushi, Gifu’s special treat in early summer. It seems to me each family in Gifu region has their own ingredients to put on sushi rice for Houba-zushi (: recipes here). i.e. no particular rule. I gathered food stored in my fridge, and made it like this:

Yayyyyy!!

Making sushi rice.
 It’s better using wooden bowel for mixing rice and vinegar,
 as the container can absorb moisture,
 which could help the rice cooling down swiftly.

First, we have to prepare sushi rice. It’s easy. Mix well 60cc of rice vinegar with 60g of sugar and 9/10 tbsp of salt. Cook 3 cups of rice in a standard way. Sprinkle the vinegar mixture over the hot cooked rice and mix well to let it cool. The point is, don’t make rice paste. You should use your spoon like cutting the mass of rice roughly. In this photo, I used Kurosu 黒酢, Japanese fermented rice vinegar which is black. My pantry did not have standard rice vinegar … Japanese black rice vinegar is made of rice only, different from Chinese version where another grains are also added. For sushi rice, I think Japanese version with simpler flavor would yield better result as we have to combine rice with the other also “simpler” ingredients as toppings.

One of the toppings I chose this time was egg. Here, I mixed well one egg with 1 tsp of sugar, then poured it over a flat plate wrapped by plastic. I microwaved it with 500w for 1 minute first. From here, the egg was microwaved little by little until its surface was done with slight moisture, like this photo. We can peel off the egg from the plastic, then julienne it as sushi topping.

This is Houba I used. This photo is for front side.

I positioned one handful of sushi rice on the back side of Houba, then put toppings on it. This time, my ingredients were julienned eggs, green beans boiled with salt (then chopped), julienned fresh Japanese ginger (Zingiber mioga), Chirimen-jako, and home-made Tsukudani from the remnants of Shiso leaves I used for Shiso Juice (my post last week). Recipe of Tsukudani is also easy. That 200g of red Shiso leaves after extracting juice was chopped and slightly stir-fried with sesame oil, then added 2 cups of water, 30g of Chirimen-jako, 2 to 2.5 tbsp of Soy sauce, and 2 tbsp of Mirin. Boil the mixture down with low heat until the liquid is almost evaporated. Any Tsukudani can be a nice topping for rice (sushi or otherwise), or filling for sandwiches. The sushi here is completed its topping with leaves of Japanese pepper (Zanthoxylum piperitum, my post on November 2^nd, 2018).

Finally, the entire sushi construction was wrapped by Houba and fastened by a toothpick. I left them overnight. It became tasty and fragrant lunch. 😋

In Niiharu, volunteers for rice paddies
 have completed transplanting rice seedlings
 before the middle of June.

Before, in Gifu Houba-zushi was for thank-you lunch to the neighbors who came to help transplanting rice seedlings to rice paddies. It was a heavy work that should have been done in a short 1-2 weeks window at the beginning of Japanese rainy season. Each community of farmers helped each other every year by planning planting schedule from one family’s paddies to the next. The return of hard work was yummy Houba-zushi. Rice transplanting season is also the season for fresh Houba falling from higher branches. I happened to meet with the very best timing to collect the leaves, just like the yesteryear farmers did for their traditional schedule. I don’t know why, but I was a bit moved by this fortune. And sushi was delicious!

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