Homemade Tomato Ketchup

Back in the days before children I used to make all of my own sauces and curry pastes. Needless to say, that rarely happens now, I tend to find that a three year old and a pile of chillies are a bad combination. But there is one thing that I do make from time to time and that's tomato ketchup. This recipe is one I have been making for years and is a combination of a few different recipes. Its also one of the only recipes I have found that uses a tin of tomatoes rather than a pile of fresh ones.

Ingredients
1 tbsp oil
1 onion
2 tbsp red wine vinegar
4 tbsp water
400g tin of tomatoes
1 tbsp tomato puree
small pinch of allspice
1/2 tsp English mustard powder
2 tbsp brown sugar
1/2 tsp salt and pepper

All you need to do is fry the onion in the oil until softened, about five minutes; then add everything else. Simmer for about forty five minutes then blitz until smooth. Pour into a sterilized jar and keep it in the fridge once its cooled. Lovely on sausage sandwiches... now that's a thought!