In a large pot with high sides, heat 1-2 tablespoons extra-virgin olive oil over medium heat. Add garlic and green onions and cook 2-3 minutes, until tender and fragrant. Add the spinach and top with the lid to the pot. When the spinach has cooked down enough to be able to stir it, stir frequently to help break it down and to prevent scorching. Cook until the spinach has completely cooked down and most of the liquid has evaporated. Remove from heat.

Add the salt, pepper, dill, lemon juice, and feta and stir to combine. Add the egg and combine thoroughly. Set aside.

Preheat oven to 350 degrees F. Melt the remaining butter. Place one sheet of phyllo dough on a clean work surface, the long side facing you, and cover the remaining dough with a lightly damp paper towel. Brush the surface of the dough with melted butter, then place another sheet on top of the first sheet and brush that sheet with butter. Using a pizza cutter, cut the dough into 5 equal pieces (about 2.5-3" wide). Place 1 scant tablespoon of the spinach-feta filling at the bottom of each portion. Fold the corner of the the dough over the filling, forming a triangle, then continue folding triangles (like you would fold a flag) and place the triangles, seam side down, on a parchment-lined baking sheet. Repeat with remaining strips and then the remaining phyllo dough and feta filling.

Brush the triangles with butter and bake for 20-25 minutes or until golden brown.