Preheat oven to 375.
Line a muffin tin with 6 liners and spray with cooking spray; set aside.
Combine water and quinoa in a small saucepan and bring to a boil; lower to a simmer, cover and continue to cook for 15 minutes.
In a large frying pan, heat olive oil over medium heat.
Add onions and cook until translucent, 3 to 4 minutes.
Stir in spinach leaves and garlic.
Season with salt and pepper and continue to cook until spinach is wilted; about 2 more minutes.
Remove from heat and let cool.
In a large mixing bowl, combine cooked quinoa, spinach mixture, cheeses and parsley.
Make sure the quinoa mixture is not warm; if it is, give it a few minutes to cool.
Pour in the beaten eggs and mix until well combined.
Divide batter evenly among prepared muffin cups.
Bake for 35 to 40 minutes, or until tops are golden brown.
Remove from oven and cool on rack.