Prepare pastry. Roll pastry into a 30 cm circle. Cover and set aside. In a medium saucepan cook potato and onion in butter over medium heat, stirring constantly, for 5-6 minutes or till onion is tender but not brown. Stir in flour, herb and 0.125 teaspoon pepper. Add broth all at once. Stir in peas and carrots. Cook and stir till bubbly.
Stir in meat. Transfer mixture to a 1.5 quart casserole. Top with pastry; trim pastry to 1 cm beyond rim. Turn under and flute edges of pastry. Cut slits for steam. Place on a baking sheet. Bake in a 220ºC degree oven for 25-30 minutes or till golden. Let stand 10 minutes.