1.Make creamy tomato sauce: Heat oil in large pan; cook onion, stirring, until softened. Add garlic; stir until fragrant. Add undrained tomatoes; bring to the boil. Reduce heat; simmer, uncovered, stirring occasionally, about 20 minutes or until sauce thickens slightly. Cool 10 minutes; blend or process sauce with cream and sugar until smooth. Season to taste.
2.Preheat oven to 180°C (160°C fan-forced).
3.Cook washed spinach in heated large pan, stirring, until wilted. Drain; when cool enough to handle, squeeze out excess moisture.
4.Combine spinach in large bowl with ricotta, eggs, 1/2 cup of the parmesan and herbs. Using large piping bag, fill pasta with spinach mixture.
5.Spread a third of the creamy tomato sauce into shallow 25cm x 35cm ovenproof dish; top with pasta, in a single layer, then with remaining sauce. Bake cannelloni, covered, in oven, 20 minutes. Uncover, sprinkle cannelloni with remaining parmesan; bake about 15 minutes or until pasta is tender and cheese is browned lightly.