Melt butter and in large frying pan or dutch oven.
Add vegetables (except peas) to pan. Cook about five minutes. Add sprigs of thyme (to be removed later).
Sprinkle flour over vegetables, Stir well.
Deglaze pan with white wine about a minute.
Stir in chicken broth. Add more if you think it's too dry.
Once chicken broth is warmed through about twenty minutes, add in heavy cream.
Add chicken and frozen peas to vegetables. Season with salt, pepper, umami seasoning (if you have it) and fresh thyme. (or herbs of your choice).
Allow to cool, while rolling out prepared pie dough.
Take pie dough out of fridge and let sit for 10 minutes.