1.) Place carrots, celery, potatoes and onions into the chicken broth and cook over med-high until tender. Add frozen peas and corn. Add diced chicken, salt pepper sage and thyme. Simmer over med-low for a few minutes.
2.) Whisk milk and flour together. Add to above mixture and simmer until thickened.
3. ) To make pie, overlap 10 sheets of fillo in a 9" pie pan, buttering the sheets as you layer them in the pie pan. Pour chicken mixture on fillo dough. Top with remaining 10 sheets, overlapping the fillo and brushing each layer. Score top.
4.) Bake in preheated 350ºF oven for 25 to 40 minutes or until golden brown Let stand 5 minutes. Serve hot.
GENERAL FILLO DOUGH HANDLING DIRECTIONS. Allow fillo dough to thaw in refrigerator overnight. Bring to room temperature before using. Carefully unroll fillo sheets onto a smooth, dry surface. Cover fillo completely with plastic wrap, then a damp towel.Keep fillo covered until needed. Do not leave uncovered for more than one minute to avoid drying out. Microwave butter until melted. This will give you a lighter and flakier pastry. Brush each layer of fillo with melted butter, margarine or oil.To prevent edges from cracking, brush edges first and then work into center. Be sure to brush the last layer of fillo with melted butter.Fillings should be chilled and not excessively moist. Fillo may be rolled and refrozen to store when not in use.