- Heat oven to 190°C.
- In a large pan, sauté the onion and garlic in butter, for about 5 minutes or until just soft. Remove from heat.
- Stir in half the cheddar, the feta cheese, mushrooms, and spinach. Mix well and place into the pie crust.
- In a medium bowl, whisk together the eggs, milk, salt, and pepper. Pour over the spinach mixture, poking holes to allow the egg mixture to seep in.
- Bake for 15 minutes. Top with the remaining cheddar and continue baking for 40 minutes, or until knife inserted in centre comes out clean.