In a large bowl, mix together the greens, dill and scallions. Add some salt and pepper. Drizzle olive oil lightly over mixture. Set aside.
In a second, smaller bowl, crumble the feta cheese. Beat in the 5 eggs until well mixed. Set aside.
Melt the butter until about half of it is completely liquid. Use your pastry brush to to spread some butter in a rectangular 9 x 13 in. pan.
Unroll the phyllo dough so that it is flat on the counter. Cover the dough with plastic wrap, and then a damp dish towel on top of the plastic wrap (don’t get the dough wet). The wet towel weighs down the plastic wrap to keep the dough fresh. When you develop some skill with the dough, you won’t need this covering step. Taking 3 dough sheets at a time, lay the dough in the pan and then use the pastry brush to brush and/or drizzle the butter over the layers. Continue doing this, 2-3 sheets at a time, until you have used about 1/2 of the thawed dough.
Now, mix the egg/cheese mixture into the spinach mixture until the greens are well-coated. Then, pour the contents of the bowl over the dough in the pan.
Continue to layer and butter 2-3 sheets of the remaining half of the phyllo dough over the filling, until you have used all of the dough.
Pour any remaining melted butter over the top of the pie. Then, lightly sprinkle the top with grated cheese.
Bake at 350°F for 40-60 minutes, until top is golden.
Remove and let cool a bit before cutting and serving.