If making a Hollandaise sauce strikes fear into you, then maybe this sauce, which is easier, will give you more confidence. The sauce, apart from being delicious with flat fish, is also great with prawns and shrimps and is surprisingly good with oily fish like mackerel and salmon. It is an immensely useful sauce that I predict you will use over and over again. It is rich, so should not be too thick when being served. I usually stir in a few tablespoons of the fish cooking water into the…