Shepherd’s Pie is one of those dishes that is typically made from leftovers, and thrown together as a tasty, hearty cost-saving measure. There are tons of different variations on the dish (for instance, in England, this would be considered “cottage pie”, since it uses beef rather than lamb), usually regional.
My variation of the dish is very simple. For the base, I make up a batch (or use leftover) of my sloppy joe recipe, sprinkle it with leftover (or frozen if I have no leftover) peas and carrots, and cover it with a batch (or leftover) mashed potatoes. I sprinkle it with sweet paprika, and then bake it for 40 minutes (or until top is lightly browned or a bit crusted). Fantastic fresh out of the oven, and just as good reheated the next day.