In a large bowl combine flour and salt. Cut in cold butter until it resemble coarse bread crumbs. Add in cold water a tablespoon at a time until the pie crust comes together to form a ball of dough.

Divide the dough to have slightly more in one piece. The larger piece will be for the bottom of the pie. Roll the dough out enough to fit the entire bottom and sides of a 9x13 pan. Place in the pan and cover with plastic wrap. Roll out the other piece of dough and place it on the top of the plastic wrap. Place the pan in the fridge to chill until ready to fill.

Preheat oven to 350.

Add peeled and diced potatoes and carrots to a medium pot to boil until tender, about 10 minutes. Drain off water and set aside.

While veggies cook, saute the chicken and onion in olive oil until the chicken is cooked through. Add in butter. Once the butter has melted, add in the flour and stir for 30 seconds. Pour in chicken broth and milk and stir until thick and bubbly.

Add in cooked veggies, frozen peas and salt and pepper.

Remove pie crusts from the fridge and take off the top piece and plastic wrap. Pour the filling into the pan and then place the top crust over the filling. Place in the oven and bake for 45 minutes or until the crust is golden and the filling is bubbly.

Let pie rest/cool for at least a half hour before serving to let the sauce thicken and cool down a bit.