Powdered sugar is a super fine sugar, finer than even castor sugar. It is often termed as 10X sugar, confectioner's sugar or icing sugar. In France, it is called Sucre Glace. The size of the sugar crystal varies 10X sugar is usually 0.010 mm, while confectioner's sugar is 0.060 mm, and icing sugar is 0.024 mm.t is a type of granulated sugar that has superfine granulated crystals, usually 0.35 mm. The term castor or caster sugar is mainly used in UK English and its Commonwealth countries. In North America, it is sold as super fine sugar.
Standard baking temperature is 350 degrees, which works just fine for fish. But you can get away with setting the temperature even lower. This extends the cooking time, which may help if other ingredients in the dish need more time to cook.
You have two main options for baking frozen fish. To dry-bake it, arrange the portions on a sheet pan lined with foil or parchment paper, then brush or spray them lightly with oil. Bake them at 425 to 450 degrees Fahrenheit for 12 to 15 minutes. Thick fillets might take a few minutes longer and benefit from being turned midway through cooking.