Preheat oven to 350 degrees F (175 degrees C). Lightly oil a 2 quart casserole dish.
In a saucepan, combine water and rice, and bring to a boil. Reduce heat, cover, and simmer for 20 minutes. Remove from heat, and stir in the spinach, egg, evaporated milk, and cheese. Spoon into the prepared casserole dish.
Bake for 30 minutes in the preheated oven, or until middle is set.