| 1 | For topping, place potatoes in large saucepan of cold, salted water. |
| 2 | Bring to boil and simmer partially covered for 20 minutes or until very tender. |
| 3 | Drain. |
| 4 | Mash in pot until smooth. |
| 5 | Add cream, butter, egg yolks, nutmeg, salt and pepper to taste. |
| 6 | Mash until smooth and fluffy. |
| 7 | Keep warm. |
| 8 | For filling, heat 1 tb. oil and butter in large skillet over medium-high heat. |
| 9 | Add onion, garlic and chili flakes; cook 2 minutes. |
| 10 | Add carrot, celery, thyme, salt and pepper to taste; cook 3 minutes. |
| 11 | Set aside in bowl. |
| 12 | Add 1 tb. oil to skillet and heat over medium-high heat. |
| 13 | Add beef and lamb; cook, stirring continuously, until meat is no longer pink. |
| 14 | Add salt and pepper to taste. |
| 15 | Discard sprig thyme and any excess fat from pan. |
| 16 | Add vegetable mixture to meat in pan. |
| 17 | Stir in stock and tomato paste. |
| 18 | Reduce heat and cook covered on low heat 15 minutes, stirring frequently. |
| 19 | Meanwhile, in separate small frying pan, heat remaining oil over medium-high heat. |
| 20 | Add mushrooms; cook 2 minutes until soft. |
| 21 | Sprinkle mushrooms on to bottom of ovenproof casserole dish, about 8 inches square. |
| 22 | Pour meat mixture over top, spreading evenly. |
| 23 | Place tomato slices on meat. |
| 24 | Either pipe mashed potatoes over meat mixture using piping bag fitted with star tip or spread potatoes over mixture. |
| 25 | Bake in preheated 375f oven 25 to 30 minutes until potatoes are golden and meat mixture is hot. |
| 26 | If potatoes are not golden, place under broiler 2 minutes. |
| 27 | Let stand 5 minutes before serving |
