1. Heat oven to 450°F. While oven is heating, combine frozen potatoes and milk in large skillet and bring to a boil over medium-high heat. Reduce heat, cover and simmer 5 minutes or until potatoes are tender.
2. Stir in leftover pork and vegetables from Peppery Country Pork Stew, mushroom soup and pimento (if using). Cook 3 minutes or until heated through. Remove from heat; cover and let stand 10 minutes to allow flavors to blend.
3. Meanwhile, unroll piecrust and place on nonstick baking sheet coated with cooking spray. (Note: the piecrust should be flat.) Prick in several areas with a fork and bake 10 to 12 minutes or until golden brown. Slide crust onto pork mixture in skillet and serve immediately.