Wasn't sure if you have Cup-a-Soup over there ... yes they are single serve sachets. I usually use cream of something or chicken noodle. The ones with lots of noodles and croutons would end up glug I'd imagine.
We used to make these when we went camping. We'd slice up the potatoe and leave it whole, slice onions and put a ring between each slit in the potato, and then wrap it all up in the foil and just throw it into the campfire. TAkes about a half hour to cook. Now at home I do what you do and lay out a square of foil. Then I'd throw on the slices of potatoes, slices of onions , and chunks of hamburg. Also throw in some cut up green or what ever color pepper and cherry tomatoes. Place a pat of butter on top of it all and sprinkle with salt and pepper and then seal. Cool in 400* oven for 45 minutes to an hour and then eat. Supercalifragilisticexpealidocious!!!!! What's nice is that each person can put what they want in their own packet. We don't put the soup in it as the veggies give it it's own flavor. My daughter makes them all the time at home in the morning and then pops them in the oven when she gets home from work. You know, I think we'll have them for dinner tonight!