Leftover mashed potatoes are awesome for making croquettes on the fly. However, there's an even speedier way to prep a batch ...

Some croquettes — including the ones in this recipe — are potato based and formed after cooking and mashing the potatoes. I know many people use leftover mashed potatoes to make them.

Leave to cool then remove the skin and the bones, then chop the fish finely and mix together with the mashed potato ... oven till you have cooked all your croquettes. Serve warm with the mustard ...