Provencal gratin of spinach and zucchini

This is a very tasty vegetarian dish that is also great with some grilled meat.

1 1/2 lb fresh spinach, washed
3 medium zucchini, grated
4oz short grain rice
2 large onions, chopped
3 cloves garlic, chopped
2 tbsp olive oil
4 Xtra large eggs
1 cup whole milk
1 cup Parmesan cheese, grated
1 cup sharp cheddar cheese, grated
2 tsp salt
a good sized pinch freshly grated nutmeg
salt and black pepper

Preheat the oven to 375F

Grease a fairly large earthenware oven dish with a bit of olive oil.
In a saute pan, cook the chopped onions and garlic until soft
Season with salt and pepper and add the zucchini and cook for an additional 5 mins until the zucchini has wilted.
Blanch the spinach in boiling, salted water for 2 minutes. Drain and refresh in cold or iced water. Squeeze out the excess liquid and chop the spinach.
Put the rice in a pan of boiling salted water and simmer for about 12 minutes.
Drain.
Beat the eggs in a large bowl and gradually stir in the milk.
Season with salt, pepper and nutmeg.
Add the zucchini, parmesan cheese, spinach and rice. Mix well.
Transfer to the earthenware dish, top with the grated cheddar cheese and bake for 30 to 40 minutes until browned on the top.
Serve