Cut the bacon in quarters and put it and the and mustard in a food processor and puree until a smooth paste consistency. Coat scallops with puree. Using a frying pan, sear the scallops in a little oil. Place scallops in the oven and bake for 8 to 10 minutes. Remove scallops and allow to rest for 2 minutes before serving. Place creme fraiche mashed potatoes on each of 4 plates and top each with 4 scallops.