Wash the spinach leaves well in a large mixing bowl and pour out the water. If any grit is left at the bottom of the bowl, repeat. Otherwise, transfer the still wet spinach leaves to a large sauté pan or rondeau. Cook, covered, over moderate heat, just until they wilt. This should take no more than a couple of minutes.

Transfer the spinach to a colander and run them under cold water. Then let them drain.

When the spinach has thoroughly drained, take them by the handful and squeeze it dry. Mince them rather finely.

Following the directions in this recipe, prepare a half batch of béchamel sauce.

Let cool.

In a large mixing bowl, stir together the spinach and bechamel. Then add the cheese, salt and pepper. Taste and adjust for seasoning, then add the eggs.

Pour the batter into a well buttered baking dish. Dot the top with bits of butter.

Place the baking dish on a large roasting pan or baking sheet and add water all around.

Bake in a moderate (180C/350F) oven for 30-45 minutes, or until cooked through and lightly browned on top. Test doneness by inserting a small knife into the sformato. If the knife comes out clean, it should be done.

If not browned on top to your liking, you can run the sformato under the broiler for a minute or two.

Let cool for a few minutes before serving.