thanks Ausgirl.

I ended up going with my instincts just then making them up (as almost ready to BBQ now) - and that's pretty much what I did - minus the carrot and zucchini, but great idea though - will definitely look at adding those next time - always trying to find ways to add extra vegies to things (not so much for DS, but for DH ) But whoops, I ended up putting all the french onion soup mix in, it is a salt reduced one, so hopefully it won't be too salty - didn't even occur to me bout that

If there is any other suggestions, still happy to hear them as we tend to have a lot of hamburgers over summer (cooked on the BBQ) - so variations would come in handy.