This is one of those recipes where you need your mis en place - everything pre-measured and chopped and ready to go because it moves pretty quickly.
Using a pan that is large enough to accommodate the prawns in one layer, melt the butter over medium heat. Add the olive oil. Then add the garlic and the chili flakes and cook for about a minute. You are not trying to brown the garlic or the butter, if either are browning you need to turn the heat down.
Add the prawns in one layer so each prawn is coming in contact with the pan. Sprinkle with the paprika. The prawns really only need about a minute before the underside turns pink and opaque. At that point, start flipping the prawns over - or just stir them, making sure that both sides are pink.
Turn off the heat and add the parsley and salt and pepper to taste.
We ate this over polenta but it could be tossed with pasta or eaten as part of a tapas meal, using bread to soak up the garlic butter sauce.