Preheat oven to 350° F. Place kale and broccoli rabe in a colander and gently squeeze out as much water as possible. Set aside.

Heat oil in a sauté pan over medium heat. Add onions and cook until soft, about 5 minutes. Stir in garlic, kale, broccoli rabe, red pepper flakes, salt and pepper; cook an additional 3 to 5 minutes. Combine onion mixture, eggs, cheese, dill and nutmeg in a large bowl. Mix until all ingredients are well-combined.

Lightly butter a 9-inch springform pan (see note). Lay a damp towel over phyllo sheets to keep them from drying out. Line the pan with one sheet of dough and brush it lightly with butter. Place the next sheet of dough on top, at a slight angle to the first, and brush lightly with butter. Continue to layer dough at an angle to the preceding sheet, until the pan is fully lined. Spoon kale mixture into the phyllo-lined pan and smooth the top. Fold dough over the top of the pie and brush with a little butter.

Bake until the filling is set and phyllo is golden brown, 30 to 40 minutes. Let cool in the pan for 10 minutes before removing the ring. Cut into wedges and serve.

Special notes:

If you don’t have a springform pan, use a 9-inch pie plate. The spanakopita will be need to be cut in slices from the pie plate, instead of removing the entire pie at once.