After a bit of experimenting, I managed to perfect freezer bag porridge.
Really nice way to start the day. And with planning, no hassle at all.
Probably teaching grandmothers about egg sucking here, but for anyone interested.....
A pre-measured bag of normal (not instant) rolled oats, powdered milk, sugar, raisins etc. Gauged to match the size of my mug.
One measure of meths in the beer can burner and boil some water. Chuck it into the bag and into the pot cosy. A damn good shake up (otherwise you get hard lumps) and leave it for 20mins. The off extra shake for luck.
If your cosy is good, you get perfect porridge that is still too hot to eat. Unwrap and eat out of the bag in the cosy.
I usually double bag the mix. Tie sandwich bags are not that sturdy and the Tesco ones I use have print on the side, which melts and glues the bag to the cosy. So double bagging, with the outer one inside out, helps. With care, you only have one of the bags mucky. So not much to burn off/bring home.