Procedure for the Béchamel: Bring the milk to the boil. In a separate pot, melt the butter over a gentle heat and add the flour. Once the milk is boiling, pour it over the butter mixture, stirring continuously to prevent lumps. Bring the béchamel to the boil, season with salt and pepper and set aside.
Cannelloni pre-cooking: Bring plenty of salted water to the boil, add the cannelloni and cook for 3 minutes. Drain and place on a flat surface, allowing them to cool. Keep the Cannelloni separated to prevent them from sticking. Do not rinse with cold water.Barilla Cannelloni can also be filled without pre-cooking. Just add a little more béchamel sauce and cook 10 minutes longer.
Procedure for the Filling: Sauté the spinach in a Teflon pan with a little bit of olive oil and a pinch of salt. Cool down and chop. In a mixer, make a filling by whizzing together roasted beef and ham. Add the spinach, the eggs, the parmesan, salt, pepper and nutmeg. Simmer. The filling should not be too hard: add a little of milk if necessary.
Assembly: SFill the Cannelloni by using a piping bag. Place them in a baking tray, previously greased with butter.
Cover with béchamel sauce, butter cubes, tomato sauce and parmesan.
Bake in a preheated oven at 180° C, for nearly 20 minutes.
Allow to rest for 10 minutes before serving.