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Make pastry, or purchase puff pastry/phyllo dough
If making dough, use this recipe and roll into 1/8 inch thick and cut to fit the pan or use round cookie cutters.
Saute 1 diced yellow onion and 4 cloves diced garlic in butter or olive oil until softened.
Add 2 TB flour, 1/2 tea oregano, 1.5 tea tarragon, 1/2 tea black pepper and cook on medium low until the flour toasts a little in the oil (for the roux).
Now add 2-3 C liquid (chicken stock and pan drippings) and veggies:
diced or cubed carrot
diced or sliced celery
optional: other hard veggies
Cook the veggies in the liquid until softened (or pressure cook).
Now add soft veggies like frozen peas or mushrooms and cooked chicken pieces. Stir to combine and take off heat. Season with salt if needed. (Optional seasonings thyme, celery seed, parsley etc.)
Spoon filling into casserole dish, pie pan or individual ramekins. Top with pastry.
Bake at 350 F for 30-45 minutes or until golden on top and filling is bubbly (like photo at top).
To Freeze for later: