Created by ImPat on November 27, 2014
Step 1: Heat the oil in a pan and add the onion and cook over a low heat for about 5 minutes, until softened but not browned.
Step 2: Add the remaining ingredients, season to taste with salt and pepper and mix well.
Step 3: Bring to the boil, then reduce the heat and simmer for 30 to 40 minutes, until thickened and then spoon into a serving bowl.