From http://www.guardian.co.uk/lifeandstyle/2013/may/10/dan-lepard-pizza-dough-tomato-sauce-recipes

Liquids evaporate quickly from a frying pan, yielding a thick, rich sauce in the fastest time and freeing you from expensive jars of ready made.

Ingredients

• 6 tablespoons olive oil
• 2 medium onions, finely chopped
• 5 garlic cloves, finely chopped
• 2 tins plum tomatoes, chopped
• 6 tbsp tomato paste
• 1 tsp chilli powder
• 2 tsp dried oregano
• Salt to taste

Method

1. Put the oil in a pan with the onions, garlic, 75ml water and a big pinch of salt. Boil until the water evaporates and the onion and garlic are sizzling and translucent.
2. Add the tomatoes and cook until almost dry, then add the tomato paste, chilli and oregano. Cook until the sauce just starts to catch on the base of the pan. Add salt to taste, then scrape on to a dinner plate to cool quickly. Use when cold. Keep what you don't use in the fridge for up to a week, or freeze.