The packed-lunching world can be divided into two segments: those who batch-cook a kilo of pasta salad on a Sunday evening, chewed with ever-decreasing enthusiasm each day, and those who prefer to have a little more flexibility with their lunch choice and are more likely to chuck things together on a culinary whim.
We belong to the latter group. Unless it's the week before payday, we like to allow ourselves a little spontaneity - a little last-minute indulgence from time to time.
So, if one doesn't have a cauldron of pasta taking up prime real estate in the fridge, which quick-fix lunch foundation is there to fall back on?
We've already extolled the virtues of the rice noodle and frozen pitta - but what about the humble can of cooked beans?
Another stalwart packed-luncher's ally, canned beans are ready to eat, so you can do as little or as much to them as you like before packing them in your lunchbox.
• Try frying some sliced garlic in extra virgin olive oil. After a minute, add a glug of white wine and a can of drained cannellini beans. Simmer the garlic and beans for 10 minutes, topping up with water or stock as necessary. Finish with a little crispy sage, fried in olive oil, scattered over the top.
• Drain and rinse a can of borlotti beans. Add chopped red onion, tomato, basil and feta. Drizzle with some olive oil, red-wine vinegar, and season to taste.
• If you're in a huge rush in the morning, you can pack up a can of black beans along with a lime, red chilli, fresh coriander, a tortilla wrap and a chunk of cucumber. Once at the office, lay the tortilla on a plate, top with the drained, rinsed beans and chopped coriander, cucumber and as much chilli as you like. Squeeze the lime juice over the top and season well.
Caroline Craig and Sophie Missing are authors of The Little Book of Lunch (Square Peg)
Cooked beans are a packed-luncher's ally... Illustration: Hennie Haworth for the Guardian