Except for the cheeses on top and the finishing touch of freshly ground pepper, this superb dish can be completely prepared up to two days in advance. It should be refrigerated, tightly covered. It is very easy to make once you've mastered the technique of the pastry bag; the alternate two-spoons method described below is a little more trouble.

• 1 cup plus 2 T milk
• 5 1/2 T butter
• 1/2 t coarse salt
• 1/4 t freshly ground white pepper
• 1 cup all-purpose flour
• 4 medium eggs
• 3 1/2 oz Gruyère cheese, freshly grated

• 1 1/2 T butter
• 2 1/2 T all-purpose flour
• 2 cups milk
• 1/2 t coarse salt
• 1/4 t freshly ground white pepper
• 3/4 cup plus 1 T cream
• 3 T freshly grated Gruyère
• 3 T freshly grated Parmesan

• 2 T freshly grated cheese
• 2 T freshly grated Parmesan cheese
• Freshly ground white pepper

Prepare the gnocchi:

1. Put the milk, butter, salt and pepper in a saucepan.
2. When the butter has melted and the mixture has come to a boil, remove the saucepan from the heat and pour in the flour all at once.
3. Replace the saucepan on the heat, stirring constantly with a wooden spoon.
4. Cook until the mixture begins to sizzle and come away from the sides of the pan.
5. Pour out onto a dinner plate, flatten with a wooden spoon, and cover with plastic wrap placed directly on the surface.Set aside to cool.
6. Bring a large pan of salted water to a simmer.
7. When the gnocchi mixture has cooled, remove the plastic wrap and transfer the mixture to a bowl.
8. Add the eggs, one at a time, stirring constantly with a wooden spoon; each egg must be completely absorbed before the next is added.
9. Add the Gruyère and season to taste with salt and pepper.
10. Fill a pastry bag fitted with a 3/4-inch tip.
11. Rest the metal tip on the edge of the pan of simmering water, then press the bag, twisting it from the bottom, and cut the mixture into 1/2-inch pieces as it emerges, using a knife. Let the gnocchi fall into the water in batches of 30; simmer each batch for 3 or 4 minutes, then remove with a slotted spoon and drain on clean tea towels.
12. Cook all the gnocchi in this way. (If no pastry bag is available, use 2 demitasse spoons. Take up an amount of the mixture the size of a hazelnut with one spoon and with the other spoon push it off into the simmering water.)

Prepare the béchamel:

1. Melt the butter in a saucepan.
2. In a blender, blend together the flour, milk, salt, and pepper.
3. Pour the mixture into the saucepan with the melted butter, then add the cream and cook, stirring, until the mixture comes to a boil.
4. Lower the heat to medium and cook for 5 minutes, stirring constantly.
5. Remove from the heat, then stir in the Gruyère and Parmesan.
6. Cover with plastic wrap placed directly on the surface of the sauce and set aside to cool.

To finish:

1. Preheat the oven to 375 deg F.
2. Put a few tablespoons of béchamel sauce on the bottom of a shallow 3-quart Pyrex or porcelain baking dish and arrange the gnocchi in one or two layers.
3. Add the rest of the béchamel, pouring it evenly over the top of the gnocchi. (Up to this point the dish may be prepared two days in advance.)
4. Sprinkle with 2 tablespoons each Parmesan and Gruyère and with freshly ground white pepper.
5. Bake for 45 minutes, or until lightly browned.
6. Serve at once.

NOTE: When you cook your gnocchi in the water they will swell; as they cool on the tea towels they shrink. When they are cooked in the oven they will swell again and should be served immediately before they have a chance to shrink.

Source:
Italian Cooking in the Grand Tradition
Jo Bettoja and Anna Maria Cornetto
The Dial Press