Pluck and wash the fresh spinach. Dip briefly in boiling salt water (blanch). Take out, drain and cut into small pieces.
Mix the minced meat with the egg, chopped bacon, mascarpone or ricotta, spinach and a dash of cream or bechamel sauce. I usually also add a dash of tomato puree and, if available, a few chopped, dried tomatoes.
Then season with herbs, possibly pesto, salt and pepper and pour into the cannelloni. This is best done with a small spoon (or fill into a plastic bag, cut off a corner).
Put the filled cannelloni in a baking dish and top with tomato puree and bechamel sauce at the end. Scatter cheese on top.
Cover with aluminum foil and leave in the oven at about 180 ºC for about 30 minutes. Then remove the aluminum foil and let the cheese brown.