I pack lunches to work on weekdays and plan my weekly menu the previous week, the same time as I order fruits, vegetables, fish and meat online. As I add items to my cart, I think of what to cook for lunch and dinner, and when to cook what, i.e., I use up the more perishable stuff, like salads, for breakfasts or lunches on Monday, Tuesday and Wednesday, and cook the iron-rich leafy greens (spinach, puay leng, cai xin) in soups for early-week dinners. I then leave cabbages, kale, broccoli and cauliflower for the later part of the week, to be used in colourful stir fries. I normally plan daily…