Preheat oven to 400°F. Spray baking sheet with cooking spray.
Mix spinach, eggs, feta, onions, parsley and dill to make filling.
Brush a sheet of phyllo lightly with butter. Gently place a second sheet on top of the first; brush it lightly with butter. Slice sheets lengthwise into 3 long strips. Drop 2 T of spinach mixture onto one end of a strip and fold one corner up to meet opposite edge and form a triangle. Continue folding the triangle up to the top of the strip (flag/paper-football style). Place pie on baking sheet and brush lightly with butter. Repeat until filling is gone.
Bake at 400°F for 25-30 minutes or until light golden brown.
NOTES: I was able to reduce the amount of butter from 2 sticks (½ lb) to ½ stick ( 1/8 lb) by brushing it on a little more sparingly. If fresh dill is unavailable, 1 T of dried dill can be substituted. I have tried this recipe with a variety of feta cheeses (domestic, French, Bulgarian, Israeli), and found the Bulgarian cheese tasts the best.
Source: hand-me-down