The San Marzano plum tomatoes are less acidic and sweeter than other varieties, their skin is thin and the pulp is thick with few seeds, these features make them perfect to prepare a fresh tomato puree.
The tomato puree is the basis to make a quick and fresh tomato sauce during the summer when the tomatoes are ripe, tasty and juicy. In Southern Italy the housewives are used to preserve the tomatoes in the jars glass (sealed and boiled) to prepare a tomato sauce to use during the winter.
How to make a fresh tomato puree:
INGREDIENTS for 4 servings:
1,5 kg San Marzano tomatoes, washed and chopped
a pinch of salt
1/2 onion, thin cut
2 tablespoons extra vergine olive oil
Put the tomatoes and some basil leaves in a saucepan, add a pinch of salt, cover and let them cook at medium heat for about 20 minutes, until they are soft. Put a vegetable mill on a saucepan, pour the tomatoes in, let the water excess goes away (after 5 minutes), and throw the liquid away. Then start turning until all the pulp has passed and the skins and seeds are left in the mill. Now you can preserve this puree or use it to make a fresh tomato sauce.
Add the oil and onion in a small sauce pan, sauté at moderate heat for 5 minutes, then add the puree, seasoning salt, cover with lid and let cook for 15-20 minutes.
Cook the spaghetti al dente, (how to cook pasta al dente: cooking basics) and then season with few spoons of tomato puree and grated parmesan cheese.