Tamagoyaki, the slightly sweet rolled Japanese omelette, is a standby protein item for bentos. It tastes great at room temperature, is fairly easy to make (once you've done it a few times), and is cheap too. Plus the cheery yellow color brightens up any bento box.

There is one drawback with tamagoyaki: unless you have a tiny tamagoyaki pan (which is a single-purpose piece of kitchen equipment, something I try to avoid stocking in my not-so-large kitchen), you need to make it with a least 2, preferably 3 or more, eggs, to produce the distinctive multilayers of egg. This is fine if you're making bentos for two or more people, but when you're making bento for one you may not necessarily want to eat 2 eggs at a time. And tamagoyaki held in the fridge for more than a day never tastes as nice.

This method of making a 1-egg tamagoyaki in a normal small frying pan was in a recent issue of Kyou no ryouri (Today's Cooking), my favorite Japanese food magazine. I've tried it out a few times now, and I'm totally sold on it. It does make a slightly flatter tamagoyaki than a multi-egg one, but it still has those nice layers.

Here's how to make it step by step.

Recipe: 1-egg tamagoyaki

You can also use the basic tamagoyaki recipe and reduce the ingredients to one quarter.

• 1 'large' egg
• 1 Tbs. water
• 1 tsp. soy sauce (regular or light-colored; here I used regular, since that's all I had in stock)
• 1/2 tsp. sugar
• 1 Tbs. bonito flakes (optional, for added flavor)
• Vegetable oil for cooking

Mix all the ingredients together well with a fork or chopsticks. Heat up a small (6 inch or 15cm) non-stick frying pan and spread thinly with oil (or use a non-stick cooking spray).

From this point on, it only takes about a minute and a half!

Once the pan is hot (if you put a droplet of water in, it dances and evaporates immediately), pour in the egg.

Stir gently with a fork or chopsticks until it's half-set.

Fold in half with a spatula.

Tidy up the other side a bit with the spatula.

Fold the one third of the egg over with the spatula. Press down.

Fold the other end of the egg over with the spatula. Press the whole thing down.

Flip over, and press again. Remove from the heat before it browns too much. (If you use light colored soy sauce, it won't get as brown.)

Cut in half and put cut side up, it is nicely multi-layered.

A 1-egg tamagoyaki is only about 100 calories and is great as a secondary protein, paired with a small piece of fish, a tiny tuna tofu burger or black bean mini burger and so on.