Foil bag dinner

OK, since Helen requested it here's the recipe for the foil bag dinner, it really is one of my favourite summer meals (plus there' s less utensils used to clean up after!)
I don't use any measurements so you have to do some guess work, just think about how much you would normally do per person (2 sausages, 1 potato, and a spoonful of carrots per personish). Also bear in mind that this recipe normally calls for farmer sausage which is smoked, not sure what the equivalent is in the UK, but I guess good old Walls will do if nothing else!

Peel and cube potatoes in to bite size pieces (you need more than you think you would, so do a little extra).
Cut in half length ways baby carrots (the pre-peeled & washed ones).
Cut sausage in to 1/4 inch think rounds, also bite size.
Dice one onion or put a couple of handfuls of dehydrated onion in.
Season with plenty of salt and pepper.
Also scatter a couple of knobs of butter in as well.

I put all this in to a Reynolds foil heat bag that I buy at Safeway, alternatively use wide foil and make a pouch to put all this in.
You need to make sure that once it's all in the bag/pouch that you fold the end a couple of times and then to seal it well, fold down the sides a couple times as well (we have been known to have spillage mid cooking when flipping the pouch).
We have only ever done this on a propane BBQ, so not sure about how the coals will work so you will just have to experiment anyways...
Put the pouch on a just lit BBQ, so the grill is still cold, on a medium heat. It should just take 30mins to cook, so you close the lid and then come back and flip after 10 mins (using oven mitts... to state the obvious), then you need to flip it every 5 minutes until it is cooked. It is also a good idea to check it 5 mins before the 30mins is done to see how it is, it may be cooked and browned already or you may need to leave it to cook for another 10 - 15mins still checking and flipping at regular 5mins breaks. Alternatively I'm pretty sure that you could do the pouch thing then cook it in the oven as well on medium heat, flipping in the same way.

I'm sorry, I'm not that great at giving instructions, but please believe me when I say that once you've done it once you'll realise how quick and easy it is.