Season & roast chicken breast in the oven at 350 degrees for 45 minutes to 1 hour depending on size of the breast. Set aside to cool. Once cooled pull chicken from bone and pull apart into small pieces.
Pre-cook veggies. Boil potatoes with skin on until tender but not all the way done. Same with the carrots. Also, microwave corn and peas. Once potatoes are cool, slice with skin on.
Melt butter in a large sauté pan, sauté shallots & garlic in butter for a few minutes. Add flour and stir until smooth and smells a bit nutty. Add chicken broth and cook until smooth and thickened. Add heavy cream and simmer for a few minutes.
Add veggies and chicken to the creamed sauce and stir gently. Add salt and pepper. If needed you may add a little extra broth if mixture is too thick but not too much.
Place pie crust in a deep dish pie pan. Pour mixture onto the bottom crust. Place a top crust over your mixture and seal around edges and cut cross slits on the top crust.