To prepare the filling for cannelloni, melt the butter in a pan and saute the spinach in it for 2-3 minutes. Stir until all the liquid evaporates.
Take off from the heat and add the cottage cheese, parmesan cheese, finely chopped bacon, cream and eggs. Season to taste with nutmeg, salt and pepper to taste and mix the filling well.
Boil the cannelloni (for about 10-12 minutes) in boiling water in a large pot with 1 tablespoon of oil. They need to soften but remain whole. Melt the butter for the sauce in a pot and fry the flour in it for a minute or two.
Gradually, add the milk while stirring. Add the bay leaf, salt, nutmeg and mustard. Stir for a few minutes and take away from the heat. Fill the cannelloni with stuffing, using an icing piping syringe. At the bottom of a tray, pour a little of the sauce on and arrange the cannelloni tightly.
Cover them thoroughly with the remaining sauce. Sprinkle with parmesan cheese and put to bake in the preheated oven for 40 minutes. When serving, you can sprinkle with more parmesan cheese and basil.