This should give you enough sauce for about 500g of dried pasta.
1kg of ripe tomatoes, roughly chopped and pureed (including seeds and skin)
3 cloves garlic. thinly sliced
6 tbsp extra virgin olive oil (we use 4 tbsp basic olive oil and 2 tbs of the posh stuff to finish)
A pinch of chilli flakes (optional)
1/2 tsp salt
Heat four tablespoons of oil over medium heat, and garlic and cook for a minute or two but don't let it colour. Add tomatoes, chilli and salt. Boil until the sauce slightly thickens (10-15 minutes) and the bubbles get a bit bigger, it should still taste fresh. Turn off the heat and stir through the rest of the olive oil. Mix through cooked pasta and serve with freshly grated parmesan.