Anyone who does any kind of art or craft work is familiar with the concept of a stash. A knitter for example has a stash of different kinds of yarn. This really helps to get the creative juices flowing. In bento making terms, the equivalent of a stash is joubisai (or johbisai) (常備菜). Literally this means 'always available food'. They are stored foods that can be kept for a while, which can be pulled out and used on short notice, and enrich and streamline the bento making process. It's a combination of what we know of as kitchen staples plus pre-prepared little tidbits, specifically meant for making bento (or any other meal, but here we'll talk about bento-specific johbisai). Japanese people who regularly make bento almost always have their own stash of johbisai secreted in their refrigerators, fridges and cupboards.

For example, I usually have several kinds of Japanese pickles and tsukudani (various foods cooked for a long time in a soy sauce based sauce) in the fridge, things like store bought furikake (though I usually prefer to make my own) and nori seaweed n the pantry, and various frozen tidbits in the freezer - mini meatballs, a mushroom mix, braised pork cubes, little stacks of pre-prepared vegetables.

Building up a bento stash is not too difficult, and you don't have to have dedicated cooking sessions to make them. Whenever I make meatloaf or meatballs for dinner, I always make something with the ground meat mixture that be used in future bentos - mini meatballs, tiny hamburgers, even mini meatloafs. I will usually pre-cook them, let them cool while I'm making the rest of dinner, freeze them on a metal tray then dump them all into a plastic freezer bag. (I'm a big fan of plastic bags because they take up minimal space.) If I blanch spinach, I'll take out some, make small bundles of them and freeze in a similar way.

Whenever you are cooking, think of ways in which you can set aside a little or make a bit extra that can be used for bento making. Just having your own stash can really ease your mind and enrich your bento boxes.

See the list at the end of this article for bento-friendly johbisai recipes.

How to keep johbisai

Refrigerated johbisai items should be well wrapped to keep odors out (or in). Unless they are preserved foods like pickles, you should never keep them for longer than a week at maximum; meat items should be used up within 3-4 days or be frozen.

When freezing, think of the nature of whatever it is you want to freeze and store accordingly. For example, anything that should be moist should be wrapped up in plastic while it still a little warm, to retain that moisture. Rice is the best example of this type of food, as are something like steamed dumplings or anything made with flour. Other items should be cooled completely to room temperature before freezing, in order to prevent a buildup of moisture and ice crystals on the surface, which may cause it to defrost in a soggy state..

Putting items in small portion-sized quantities on a metal tray helps them to freeze very fast, which is what you want to do. It also helps to keep each portion separate once you pack them into well-sealed plastic bags or containers.

Try to use up any frozen cooked food within a month for optimum quality.

Build your stash up slowly

Don't get too hung up on growing your bento stash though. As long as you have at least a couple of things stored away that you can pull out when needed, that's fine. I'd really like people to get away from the idea that you need to get together a lot of 'stuff' before embarking on their bento making adventures! Just take it easy and jump in!

A few of my favorite storebought stock items

In the freezer:

Frozen peas

Frozen edamame, both in the shell and shelled

Frozen mixed vegetables of all kinds, such as peas and carrots

Frozen uncooked shrimp, peeled or whole

Frozen berries

Seeds like sesame and sunflower. I find they can turn rancid fast at room temperature, so if I buy a big bag of sesame seeds, I put it in a plastic container with a lid and freeze it. I can just scoop out what I need.

In the refrigerator:

Japanese or Western pickles and cornichons (once opened)

Miso, kochujang, and other miso-like pastes (once opened)

Umeboshi (pickled plums) (once opened)

Eggs. Always have some eggs.

Fresh ginger

In the pantry:

Vegetables that can be kept out of refrigeration: onions, garlic, potatoes

Various canned goods, especially tuna, sardines, salmon, anchovies, all kinds of beans, certain vegetables (corn, tomatoes)

I stock various dried Japanese foods like seaweed (nori, wakame, konbu, hijiki, tororo konbu), dried tofu (kouya dofu) and dried daikon radish (kiriboshi daikon), but these are strictly optional. Very convenient though!

Furikake (optional)

Soup stock cubes or granules, dashi stock granules

Soy sauce

Mirin and sake (optional unless you make a lot of Japanese food)

Vinegars - I have rice, red wine and balsamic right now

Salt, pepper

Various spices such as dried red chili pepper flakes and powder, nutmeg, cinnamon, paprika (hot and sweet), turmeric, curry powder, garam masala mix, cumin, coriander, cardamon, sansho pepper, and on and on...

Dried herbs: Thyme, rosemary, Herbes de Provence mixture

Flour

Cornstarch or potato starch

Oils - olive, sesame, neutral flavored cooking oil such as canola or sunflower or peanut

Agar-agar powder

Sugar or sugar substitutes and other sweeteners like honey, maple syrup, agave syrup

Ketchup

Tomato paste

Worcestershire sauce

"Bulldog" sauce (Japanese steak or tonkatsu sauce) (optional)

Hoisin sauce (optional)

Sriracha sauce or chili sauce of your choice (e.g. harisa)

Rice (brown and white) and other grains like quinoa, millet, amaranth, barley

Dried beans - red kidney, chickpeas, white beans, azuki beans

Dried pasta

Nut butters

Raw nuts - almonds, pine nuts, cashew nuts (use up before they turn rancid)

Dry crackers and long-keeping bread like rye crackers and those little round breads you can get at Ikea

See also