Preheat the oven to 200C/400F.
In a large skillet, heat up some olive oil and cook onions for 5 minutes, add in garlic and spinach, cook for 5 minutes more. Season the mixture with salt, pepper, chili and dry italian herbs, mix well, cook for 2 minutes. Let cool down.
300 g 10 oz frozen spinach, thawed and dried, ½ white onion, 3 tablespoon olive oil, 3 garlic cloves, 1 teaspoon chili flakes, 1 ½ teaspoon dry italian herbs
Whisk eggs with parmesan, sour cream, salt and pepper. Mix in spinach filling with feta and transfer into the casserole or pie dish.
¼ cup parmesan, ¼ cup sour cream, 6 eggs, 200 g 7 oz feta cheese, cut into cubes
Combine breadcrumbs with olive oil and parmesan. Sprinkle the mixture on top.
⅓ cup breadcrumbs, 2 tablespoon olive oil, ¼ cup parmesan
Bake for 35-40 minutes. Let cool down before slicing.