Place onion in a pan with a drop of oil and fry gently for 5 min, add garlic and fry for 2min.
Add tomatoes and cook for 10 to 15 min, until thickened, then add the tomato puree and basil.
Put spinach in a frying pan and wilt, cool, and squeeze out any excess water.
Mix with the cheese and seasoning.
Lay the sheets on a board, put the spinach on top and roll up. (You can use 1 sheet of lasagna per person or cut the sheet in two and make two smaller ones per person).
Put the tomato sauce into a baking dish and lay the cannelloini on top and cover with cheese sauce and grated parmesan.
Bake in a hot oven for 30 min.
Serve with green salad.