Eggnog should normally be thick enough to coat the back of a spoon. If yours isn't thickening, chances are you just need to keep cooking it for a bit longer. If you're feeling like it just isn't happening and you want to give up (we've all been there!) don't worry, your drink will still have loads of flavour even if it is a bit on the thinner side. To be sure that the egg yolks are cooked adequately,