Scatter the potato over the top of the pie, leaving a rough topping rather than pressing it down. Coarsely grate the sweet potato. Learn how to cook great Fish pie with sweet potato . Fish pie with sweet potato recipe. Sweet potatoes can be cooked in similar ways to the potato but cook much more quickly. Good appetite! Get one of our Fish pie with sweet potato recipe and prepare delicious and healthy treat for your family or friends. Crecipe.com deliver fine selection of quality Fish pie with sweet potato recipes equipped with ratings, reviews and mixing tips. They are also prone to burning because of the sugar content. Melt the butter in a pan & add the potato. Place in a clean tea towel & squeeze out the excess water. Stir over a medium heat for a couple of minutes until the potato is coated in Butter & starting to soften.