Testing - Leftover Lamb Pot Pie

What to do with leftover lamb/mutton hotpot? Expecially when one didn't get the flavouring right? Make it into a pie! In searching the internet, and consulting my books, I believe the best solution to this conundrum is to us the Leftover Chicken Pot Pie recipe and adapt it to lamb. Here goes!
1 - That worked out well. I think any future attempts will depend on the type of recipe used to cook the meat - a liquidy stew vs. a dry stew vs. a roast with dripping etc. Hmmm, how to write instructions on how to make the sauce from such different types of gravy?

1 small potato, diced (can use cooked or raw)
1 small onion, diced
1 stalk celery, diced
1 carrot, diced
1 Tbsp butter
1/2 cup white wine
1 Tbsp fresh rosemary, minced
1 cup lamb/mutton gravy (from leftover stew/hotpot)
1/2 cup crème fraîche
1 Tbsp Worcestershire sauce
1 teaspoon salt
1/4 tsp. pepper
2 heaping cups lamb/mutton, cooked and chopped
A handful of chopped parsley
2 batches of pie crust, uncooked

1. Preheat oven to 400°F.
2. Sauté onion, celery, carrots and potatoes in butter until cooked through and starting to brown, about 10 minutes.
3. Add the wine and cook until completely evaporated. Add the rosemary and cook about a minute.
4. Combine the broth and the crème fraîche and Worcestershire sauce. Dump into the vegetable mixture and stir thoroughly. Stir in the salt and pepper. Cook over medium heat stirring constantly until the broth thickens and gets bubbly.
5. Mix in the meat and parsley and stir to combine well.
6. In a shallow pie pan lined with uncooked dough, pour in the meat mixture and top with the remaining pie dough. Cut slits in the crust to allow steam to escape. Bake for 40-50 minutes or until the pastry is golden brown and the filling is bubbly and heated through.