Heat the oven to 375ยบ.
Have 4-6 sheets of filo leaves defrosted and covered, ready to use.
In an ovenproof 12" skillet, heat 8 T butter and once it's melted, remove 2-3 T to a small bowl to use later.
In the remaining butter on medium heat, saute:
1 cup minced onion
2 cloves minced garlic
2 cups chopped mushrooms (I used standard button mushrooms but any type would be good)
Saute for 10-15 minutes, until wilted, but not browned. To this, add 16 oz. chopped fresh baby spinach (If you're using frozen chopped spinach, defrost and squeeze ALL the liquid out) and stir, cooking another 5 minutes. Spoon this mixture into a mixing bowl.
To the spinach mixture, stir in 3 beaten eggs, 1-1/2 cups ricotta cheese (I used whole & not skim), 1/2 cup crumbled feta cheese, 1/4 tsp. fresh minced dill, 1/2 tsp. fresh minced marjoram and S&P to taste. Add a dash of nutmeg if you like (I don't like).
Return to skillet making sure you leave some space against the edge of the pan.
Cut the filo leaves in half. Take one at a time and brush it with melted butter - then layer it onto the spinach mixture. Do this one at a time (butter side down) and when they're covering the spinach (overlapping onto one another) finish up by tucking the ends under the spinach at the edge of the pan. Messy and uneven is fine! :)
Bake for 40-45 minutes, or a bit longer if you like the pastry darker. Remove, cook a bit and cut into wedges.
