1. Cut the mushrooms into small bite-size pieces and finely cut the garlic and ginger.
2. Heat a tsp of oil in a saucepan on medium heat, when the oil is hot add two-thirds of the garlic and ginger and sauté this for a minute.
3. Add the mushrooms to the pan and cook this for 6-7 minutes.
4. Once the mushrooms have cooked, add the spinach, a pinch of salt, and a pinch of pepper, and cook for 2-3 minutes or until it's slightly wilted.
5. Turn the heat to low-medium and add the ricotta, followed by the lemon zest. Stir the mixture together and sauté for another 2-3 minutes. Then turn the heat off, and allow the mixture to cool for 30-40 minutes.
6. Add the tinned tomatoes, oregano, mixed herbs, salt, pepper, and the rest of the garlic and ginger to a blender and blitz until it is a fine sauce. (If you do not have a blender, grate the garlic and ginger and squish the tomatoes using the back of a spoon).
7. Grate the cheese and leave it aside.
8. Preheat the oven to 180 degrees.
9. Layer half of the tomato sauce into an ovenproof dish.
10. Fill each of the cannelloni tubes with the mushroom mixture and place this on top of the tomato sauce.
11. Once you have placed all the tubes into the dish add the rest of the tomato sauce (making sure it covers all of the tubes) and layer with the grated cheese.
12. Put this into the oven for 30-40 minutes or until the cheese has melted and is golden brown.
13. Serve with a mixed leaf salad.
14. Enjoy!