In a saucepan heat the olive oil; add onion and garlic and cook until soft and golden.
Add tomatoes; season with sugar, salt and chilli. Simmer over low heat approximately 20 minutes; until the sauce slightly thickens.
To prepare the fennel, trim off the green tops and peel off the tougher outer layer.
Cook in boiling water for approximately 10 minutes. Let cool and cut the bulb into quarters.
Place in an oiled baking dish and coat fennel in tomato sauce.
Roast at 180C for approximately 30 minutes; Fennel should be tender and nicely browned.
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