Varies.
Sometimes I buy lunch out, anywhere between a gourmet pie or a burger from a chip van.
If I take it I buy fresh baguettes from the bakery and fill with something decent, lots of salad on top. Always make it good though, pastrami, prosciutto, provelone, pepperoni. Little oregano or chilli vinegar in that badboy and some salad and it's god tier.
I did for a while take homemade soup and a couple of rolls, cooked it on a camping stove but I stopped that when the gas cannister started leaking in my van.