, (white and green parts separated)
, coarsely chopped (2 cups)
SQUEEZE spinach to remove liquid. Heat 1 tbsp oil in a large frying pan over medium. Add green parts of onions and cook until wilted, 2 min. Stir in spinach and cook until hot, 2 min. Transfer to a bowl and stir in 1/2 cup feta.
WIPE pan clean and return to heat. Place 1 tortilla in frying pan. Scatter quarter of spinach mixture over half the tortilla. Fold other half over filling. Cook, flipping halfway, until golden, about 2 min per side. Repeat with remaining tortillas and filling.
STIR cucumber, tomatoes, white parts of onions, 2 tbsp lemon juice, and remaining oil and feta in a large bowl.
COMBINE sour cream, lemon zest, remaining lemon juice, dill, garlic and salt. Serve quesadillas with sauce and Greek salad.