Preheat the oven to 200c and put a baking tray to one side.
Melt the butter in a saucepan and add the spinach, cook for 1-2 minutes until wilted, then remove from the heat, cool and chop.
Place the egg one bowl, the flour, salt and pepper in a second bowl, and the breadcrumbs in the third bowl. Sprinkle the paprika onto the breadcrumbs and then drizzle the oil on too. Mix the breadcrumbs, paprika and oil together so the oil absorbs into the breadcrumbs.
Place the mashed potato in a bowl and add the chopped spinach and goats cheese. Mix together until just combined. Take a heaped tablespoon of mashed potato mixture and shape into a cylinder. Dip the croquette into the flour, then into the egg and finally into the breadcrumbs, ensuring the croquette is completely covered. Place on the baking tray and repeat until all of the mixture is used.
Ensure there is a little space between each of the croquettes on the tray, then place in the oven for 15-20 minutes until the croquettes are golden.
Take out of the oven and arrange on a plate, then sprinkle with parsley. Swirl the crème fraiche and sweet chilli sauce together and serve with the croquettes.