Chana masala

A chickpea curry in a tomato-based sauce, a staple of North Indian and Pakistani cooking and one of the cheapest lunches on this list. Canned chickpeas cut the cooking right down, and they hold their shape for days instead of breaking down. It tastes good warm rather than piping hot, which helps when the office microwave line is long. Rice is the easy partner, but naan or whole-wheat flatbreads packed separately keep the week varied. It is naturally vegan, and a spoon of yogurt on top adds creaminess and a little extra protein for anyone who eats dairy.