Dice the onion, and finely chop the chilli and garlic. Place into a large, oven proof roasting tray, mix with the olive oil and spices, cover with foil and roast for 20 minutes.
After 20 minutes, remove from the oven, add the rest of the ingredients to the roasting tray and stir thoroughly.
Roast for another 45 minutes, uncovered this time, then take out of the oven and stir. If needed, add up to 1/4 cup of water to thin out the sauce.
Notes
Store in the fridge in an airtight container for up to 5 days, or freeze for up to 3 months. Reheat thoroughly before serving