@coffeehabit does it not break the casserole dish? My slow cooker is huge so will try that.
Put a folded tea towel under the smaller casserole and pour an inch of water around if you are worried.Mine has a metal 'dish' so not likely to crack but I do this for steamed puddings.
Argos do a small slow cooker 1.5 litres.
Just a thought on slow cookers - if you make chicken stock, use a SC liner, add the chicken carcass, onions etc for your stock.
Once cooked allow to cool, get a bowl or large jug, pot a sieve on top, put the entire sc liner with bones etc in the sieve and cut a hole, the stock will drain quickly and you can throw the liner away with little mess.
SummersB
Forget the cling film, grease the ramekin and crack the egg into it, use a knife to pierce the yolk and microwave on low for 2 mins.
And in a link to slow cookers and breakfast, you can make a cooked breakfast over night in a slow cooker, you need to roll the bacon and if you are doing beans put them into a mug.