Prepare all of the ingredients. Preheat oven to 425deg.
In a large pot over medium high heat, add half a stick of butter, onions, garlic, rosemary, thyme, salt and pepper. Cook for 3 minutes then add chicken. Cook for 5 minutes., stirring often.
Reduce heat to medium and push contents of pot to one side. Add half stick of butter. Once melted, whisk in flour and let cook for 3 minutes. Then whisk in chicken broth. Combine all contents of the pot and add peas & carrots. Let cook for 3 minutes and stir in heavy cream.
Transfer contents of the pot to a 13 x 9 baking dish. Melt remaining half stick of butter. Place puff pastry sheets over top of baking dish and brush with melted butter. Sprinkle with parsley. Place in oven for 30 minutes.