Updated April 2, 2016.

While on my squash spree last month, I picked up a spaghetti squash, which has a great name in Japanese, too: soumen kabocha (そうめんかぼちゃ), like soumen noodles, or kinshiuri (金糸瓜), “golden thread squash.” This was my first time cooking this type of squash, and I had no idea what to do with it. First, I tried eating it like spaghetti and made a tomato sauce for it, but it came out like Italian-inspired coleslaw, which was pretty okay on lentil burgers.

My searches of all the blogs, cookbooks, and cooking sites I use didn’t turn up much in the way of other recipes that I felt like eating and I didn’t have the time to hit or budget the store for more ingredients. Maybe I’d use it in a “leftovers” food like stir-fry, or–great idea #1–okonomiyaki. Without any cabbage, which I rarely have in stock, I hit on great idea #2: forget the cabbage, the squash would be the vegetable base.

The great thing about using spaghetti squash in okonomiyaki is that the batter helps with the texture, making it easier to eat. Plus, the squash is a little more flavorful than cabbage, and it also pairs well with so many other ingredients that you can dress it up however you like. You could use okonomiyaki standards like mixed seafood, or flavors that pair well with squash like mushrooms and salmon; the squash also goes well with okonomiyaki sauce and mayonnaise. Finally, spaghetti squash is cheap (in Kanazawa): one 600-800-gram squash will cost you about 50-200 yen. (Cabbage is cheap, too, but you won’t break the bank trying to spice your dinner up a bit with this squash.)

If you cook the squash ahead of time, this meal can come together in about 15 minutes. I’ve included instructions for cooking the squash, the okonomiyaki, and for optional add-ins below. I use store-bought okonomiyaki flour, which contains some fish-based seasoning, but this recipe can be made from scratch to be completely vegetarian (or if you can’t buy okonomiyaki flour): see Just Hungry for batter recipes.

How to Cook Spaghetti Squash
I find boiling works best in my kitchen, but one may also use the oven or microwave. Reference: “How to Cook Spaghetti Squash” on food.com.

Boiling: 20-30 min.
1. Set a large pot of water to boil.
2. Rinse the squash and cut in half along the equator.
3. Boil squash for 20-30 minutes or until the skin can be pierced by a fork.
4. Remove squash and drain well. When cool enough to handle, scoop out seeds and pulp. Remove the strands of squash by using the tine of a fork to gently twist the squash off the skin. Set aside.

Oven: 60-90 min.
1. Rinse squash. Cut lengthwise and remove seeds.
2. Place in a roasting pan with about 2 cm of water.
2. Cook at 190°C (375°F) for 1 – 1.5 hours or until the skin is easily pierced by a fork.
4. Remove squash and drain well. When cool enough to handle, scoop out seeds and pulp. Remove the strands of squash by using the tine of a fork to gently twist the squash off the skin. Set aside.

Microwave: 20 min.
1. Rinse squash. Cut lengthwise and remove seeds.
2. Place in a roasting pan with about 2 cm of water.
3. Cover in plastic wrap and cook on high for 10-12 minutes.
4. Let stand for 5 minutes before removing plastic wrap.
5. Remove squash and drain well. When cool enough to handle, scoop out seeds and pulp. Remove the strands of squash by using the tine of a fork to gently twist the squash off the skin. Set aside.

Leftover cooked squash will keep in the refrigerator for 3-5 days or in the freezer for 10-12 months.

Spaghetti-Squash Okonomiyaki

Makes 2 okonomiyaki

Ingredients
100 g (3.5 oz) okonomiyaki flour (okonomiyakiko, お好み焼き粉）
200 g (7 oz) spaghetti squash, cooked (soumen kabocha, そうめんかぼちゃ; or kinshiuri, 金糸瓜)
1 egg (tamago, 卵）
1/2 stalk of green onions or to taste (negi, ネギ)
100 mL (1/3 cup + 1 TBSP) water
Other add-ins (see below)

~1 Tablespoon sesame oil (for cooking) (goma abura, ごま油)

Condiments
~2 Tablespoons okonomi sauce (okonomi sôsu, お好みソース）(1 per okonomiyaki)*
~2 teaspoons Japanese mayonnaise（mayonêzu, マヨネーズ) (1 per okonomiyaki)**
A sprinkle of nori (dried seaweed)（aonori, 青のり）
Katsuobushi (dried bonito flakes), to taste（katsuobushi, カツオブシ, 鰹節）

Equipment
1 large frying pan
2 spatulas

Procedure
1. Dice the cooked squash into small pieces–this will make the okonomiyaki easier to eat and less stringy. Dice green onions and any other add-ins as appropriate.
2. Combine flour, squash, egg. onion, other add-ins, and water. Stir well to combine.
3. Heat a little sesame oil in the frying pan. When hot, add half of the batter and spread into a pancake shape.
4. When the sides firm up and the bottom browns a little, use spatulas to flip the okonomiyaki. Cook other side until the pancake is cooked through.
5. Remove okonomiyaki to plate. Repeat for second okonomiyaki.
6. Garnish with okonomi sauce, mayonnaise, nori, and/or bonito flakes. Serve hot.

Suggested Add-ins
This okonomiyaki is fine as-is, but you can add other vegetables, mushrooms, and meat to it to use up leftovers or make it more interesting.

Note: If using meat, I like to cook mine, dice it, and mix it in with the batter for this recipe. You can cook yours in the same pan immediately before cooking the okonomiyaki or use leftovers.

1 trumpet mushroom, diced (eringi, エリンギ)
a handful of maitake mushrooms, diced (マイタケ、舞茸）
100 g (3.5 oz) salmon, flaked (shake, sake, 鮭)
50 g (1.5 oz) ham, diced (I use leftover coldcuts) (hamu, ハム)
1 Tbsp pickled ginger, minced (beni shôga, 紅ショウガ）
30 g (1 oz) shredded cheese (nachuraru chîzu, ナチュラルチーズ)

If you come up with any favorite add-ins for this dish, please comment!

Nutritional Information
Serving size: 1 pancake. 285 calories. Nutritional information is for just the okonomiyaki, sauces, and bonito flakes with no additional add-ins.

I normally use Calorie Counter, but I couldn’t because of the Japan-specific ingredients, so I used EiyouKeisan.com and the sauce websites (below) to get the calorie information.

Notes
*I like Otafuku brand (オタフク).
**Most people use Kewpie (キューピー); I prefer Pure Select Super Low Calorie, Calorie 70% Cut (ピュアセレクト®　スーパーローカロリーカロリー７０％カット) (the one with a green cap) because it is lower in calories and has a longer shelf life. I almost never use mayonnaise, so it takes me forever to get through a bottle.