1. Preheat oven to 375 degrees. Spray a shallow pie dish with nonstick spray. Slowly roll out one pie crust round over the bottom of the dish.

2. For the filling: In a large pot over medium heat, melt butter. Add onions and carrots and cook until vegetables are beginning to soften, about 10 minutes. Stir in garlic, and then stir in flour and cook for another 2-3 minutes. Gradually whisk in chicken broth.

3. Bring mixture to a boil and cook until thickened, about 5 minutes. Stir in heavy cream, chicken, peas, parsley and thyme. Season mixture with salt and pepper.

4. Pour mixture into the prepared pie crust. Roll the other pie crust round slowly over the top of the filling. Pinch edges all round the dish to seal it to the other crust. Cut off any excess.

5. Lightly beat 1 egg and 1 teaspoon water together, then brush over the top of the pie crust. Sprinkle sea salt over the top as well. Then cut 4 slits into the top for steam to release.

6. Bake for about 45 minutes or until the crust is golden brown. Let cool for at least 15 minutes before serving.