When I remove my crème caramel from the ramekin, there's always toffee left in the base... it never comes out clean. What can I do to prevent this?
Unfortunately, you'll always have caramel left in your ramekin or dariole after turning out a crème caramel. It's the nature of the beast: caramel sets hard and likes to stick when cold. If you can turn out a crème caramel with a nice top layer of caramel-scented cream and some caramel runs over to sauce the crème, then you're off to a good start.
There are a couple of things you can do to remove any extra caramel from the mould:
1. Heat your oven before turning your crème caramels out and return the ramekins to the oven to melt any caramel left
2. Have a bath of boiling water ready in a baking dish and sit the empty moulds in it for a minute or two which will also melt some of the caramel down.
Take into consideration that you probably won't extract all the caramel, but a little extra is always better than none.
If you need a break from crème caramels, here are some more caramel recipes to try.