Place thawed phyllo on floured surface slice into 2" wide strips brush with butter and place on heaping tbsp. of potato mixture on phyllo fold phyllo into triangle pkgs
Preheat oven to 375 °F
Repeat with potato mixture until all is used up brush with 1 egg beaten and sprinkle with coarse salt
Bake at 375 °F for 10-15 minutes, or until golden brown.