There's a new "food trailer" that's in the Walter Anderson Nursery lot in Poway (it apparently opened earlier this month). I ate there today for the first time -- it was my wife's third time there. They have a wide variety of sandwiches there, with all but one priced at $9 which included a very large sandwich, your choice of drinks, and a small fruit accompaniment on the side (today was strawberries). Their facebook page (https://www.facebook.com/GardenCafePoway) has a good picture that shows the set-up.
My initial thought when I saw the $9 on the white board with all the sandwiches was the price was a little high, but then when the drink was included and their was no tax added (i.e. it was already in the price), and then had a large sandwich that tasted great, I revised my thinking such that the price is very fair.
They source local, and had great bread. Only have one picture though the four of us all had different sandwiches and everyone said theirs was great. Each sandwich used a different type of bread.
If you are in the area you should try it. Only open Tues thru Sunday, 10 am to 3 pm weekdays, 9 am to 3 pm weekends