Turkey Pot Pie with Puff Pastry

Name: Turkey Pot Pie with Puff Pastry
Prep time: 35 min
Cook time: 30 min
Total time: 1 h 5 min
Cuisine: American
Ingredients: 1/4 cup unsalted butter; 1 1/2 cups 1/2" diced carrots; 1 cup 1/2" diced celery; 1/2 cup 1/4" diced onion or pearl onions; 1/4 cup all purpose flour; 3 cups hot chicken broth; 1 1/2 cups 1/2" diced potatoes (I used quarted red baby potatoes with skin); 1 tsp finely chopped fresh thyme (or 1/2 tsp dried); 1 tsp finely chopped fresh parsley (or 1/2 tsp dried); 1/4 tsp kosher salt; 1/4 tsp pepper; 2 cups 1/2" diced cooked turkey or chicken; 1 cup frozen peas; 1 sheet pre-made puff pastry; 1 large egg; 1 tbsp cream or milk