Need to cook for 12+ people and am looking for a good, tried and true recipe for Australian Shelpherd's Pie made with lamb.

Aussie Shepards Pie 1 ounce butter 2 onions (finely chopped) 1/4 cup plain flour 1 teaspoon Dijon mustard 1 1/2 cups chicken stock 2 lbs lean ground lamb 1 tablespoon worcestershire sauce salt pepper 1/2 cup hot milk 1 ounce butter salt pepper 4 large potatoes, cooked and mashed Grease an 8-cup capacity casserole dish. Preheat oven to 210°C (425°F). Melt butter in a large pan, add onions and cook until golden brown. Add flour and mustard to the pan and stir for 1 minute, gradually add the stock and stir constantly until smooth. Bring to the boil and then reduce heat and simmer for 3 minutes. Add the meat and Worcestershire sauce to the pan and stir. Season to taste, remove from heat and spoon into the casserole dish. To make potato topping, combine all remaining ingredients, mix until smooth and creamy. Spread the mixture evenly over the meat and rough up the surface with a fork. Bake for 45 minutes. I've made this pie for my family on a number of occasions and have never been left with 'leftovers'. Enjoy

Australian Shepherd's Pie 1 kg minced lamb 1/4 cup olive oil 1 cup carrots 1 cup mushrooms 1 cup celery 1 cup frozen green peas 1 cup frozen corn 2 onion 4 cloves garlic 2 Tbs Dijon mustard 2 Tbs Worcestershire sauce 1/2 cup chicken stock 1/2 cup dry white wine salt black pepper 1/4 tsp allspice 2 Tbs cornflour 1.5 kg potatoes white pepper 1/4 cup sour cream 80 g tasty cheese 1/4 cup tomato paste 1 Prep: Finely dice carrots, onions and celery. Finely slice mushrooms. Peel and dice potatoes. 2 Add potatoes to boiling water. Cook 15 minutes or until tender. Drain. Mash potatoes with sour cream, cheddar cheese, salt and white pepper. 3 Add olive oil to large frying pan and heat. Cook beef, onions, mushrooms and garlic until no pink remains in beef. Add carrots, peas, celery and corn and cook until vegetables are softened. Mix cornstarch with wine and stock and add to beef and vegetables. Add Dijon mustard, allspice and season to taste. Mix well and cook until gravy has thickened. 4 Put meat and vegetable mixture into 2 x 1ltr casserole dishes. Cover with mashed potatoes. Dot with a little butter. Cool in the refridgerator and then transfer to the freezer. 5 Defrost well before baking, uncovered in a moderate oven for 40 minutes and the potato topping is golden JM