Cook ravioli in large saucepan of boiling water, until just tender, following packet instructions.
Meanwhile, heat oil in a large frying pan over medium heat. Add onion and garlic and cook, stirring, for 3 minutes or until onion softens. Add paste. Cook, stirring, for 1 minute or until fragrant.
Add tomatoes. Bring to the boil. Reduce heat to medium and simmer, uncovered, stirring occasionally, for 6-7 minutes or until the sauce reduces and thickens slightly.
Stir in sugar and basil. Transfer to a food processor. Process until smooth. Return to pan. Add cream and 3/4 cup (100 g) of the parmesan. Stir until heated through and combined. Season with salt and pepper. Add ravioli. Toss to coat.
Serve ravioli topped with remaining parmesan and basil leaves.