This is a recipe how to make traditional Italian cannelloni from scratch. It requires time but you can easily spread the preparation over 2 days (one for bechamel, tomato sauce and pasta dough, the other for assembling and baking). Or, to skip a step, use store bought cannelloni.
To save some time and work, you can roll out the dough thinner, about 3mm, up to the next to the last setting of the pasta machine. This way, you won't need to blanch the dough before filling. Be careful, because the dough will be really thin and rip easily.
You can prepare the cannelloni up to 2 days in advance, refrigerate and reheat in the oven for 10 minutes before serving. They are also great to freeze.