You may have heard of a citrus fruit called yuzu, that has been on all kinds of trendy restaurant menus in the past few years. It is in fact one of many humble citruses that have been in use in Japan for a very long time. Yuzu trees are very slow to mature to the point where they can bear fruit, so fresh yuzu are rare and expensive outside of Japan.

Dried yuzu peel and bottled yuzu juice are somewhat more accessible, but still very expensive. But yuzu has such a distinctive, delicious aroma that they are well worth the trouble and cost to get them.

I managed to get some fresh yuzu this week, which I used for this super-simple Japanese-stye pickle recipe. Around 10 minutes of effort will reward you with several days' worth of crunchy, tasty vegetables with a refreshing citrus-y kick to tuck into your bento as a salad or side vegetable, or just to eat at home.

While I've given you several Japanese-style pickle (tsukemono) recipes in the past, both here on JustBento as well as on Just Hungry, in particular the this 'instant pickle' series, this has to be my easiest recipe yet. I can prep it in a jiffy even when my energy level was low, or just hand the task to The Guy. Plus it's a great way to make myself eat a lot of vegetables when my appetite just isn't there. The beauty of having a batch of 'instant pickles' in the refrigerator means that there's always some vegetable ready to pack.

You can use any kind of crunchy vegetables that you might eat raw in a salad for this, but cucumber should always be included. Radishes, daikon radishes or mouli, and small white turnips will work well.

If you can't get a hold of dried or fresh yuzu peel, note the suggested substitute of grapefruit peel plus lemon peel.

Recipe: Yuzu scented winter vegetable tsukemono (pickles)

Prep time: 10 minutes

This makes enough for several bento-sized portions.

• 2 English cucumbers (the long kind that often comes shrink-wrapped in plastic), cut in half lengthwise, de-seeded and cut into chunks
• 2 medium carrots, peeled and sliced thinly (about 1/8" / 1/4 cm thickness)
• 3-4 cabbage leaves, roughly chopped (including the ribs, which can be thinly sliced and added)
• 1 small piece fresh ginger root, peeled and thinly sliced
• The peel of 1/4 yuzu fruit OR 2 teaspoons dried yuzu peel OR a piece of grapefruit peel plus a piece of lemon peel (unwaxed) without the white pith
• 1 teaspoon sea salt
• 2 teaspoons yuzu juice OR lemon juice
• 1 teaspoon soy sauce
• 1 teaspoon whole black peppercorns
• 1/2 teaspoon instant dashi stock granules (optional)

Note: When you take the peel off the fruit, take care to leave off the white pith, which will impart a bitter flavor. You just want the flavorful oils that are in the peel.

Put all the ingredients inside a large, sturdy plastic ziplock bag. Close securely, taking out as much air as possible. Gently massage the bag so that the seasonings permeate the vegetables and the peel(s) release their oils, while you turn the bag over several times.

Leave the bag in the refrigerator for at least an hour, preferably overnight. Drain off any liquid before packing into a bento box, or use a leak-proof side container. If you think it needs more seasoning, add a tiny bit of salt or soy sauce.

This will keep in the refrigerator for up to a week, right in the bag. Turn the bag over whenever you remember to (at least once a day or so). If the bag develops a leak, put it in another bag and put a plate underneath so that it doesn't leak out into your refrigerator.