1. Cook potatoes in salted water. Drain, let cool and remove skins.
2. Mash in large bowl with butter, Half & Half, sour cream, and season to taste with 1/2 tsps. each salt and pepper. Spur cream is optional but does add flavor to the potatoes. Set aside.
3. Saute beef until browned and crumbly. Season to taste with 1/2 tsps each of salt and pepper.
4. Add tomatoes, mushrooms, parsley, tomato paste, Worcestershire and gravy. Stir to mix.
5. Add peas and cook about 5 minutes.
6. Fold mixture into casserole dish.
7. Spread potatoes evenly over meat. Bake at 400 degrees 40 minutes until top is crispy brown.