I need 1/2 cup of tomato sauce.
How much tomato paste plus water can I use to get the equivilant.
Thanks to anyone that can answer this.
Hi busyfingers,
IMHO, NONE.
Tomato paste plus water will give diluted tomato paste and not a sauce - just buy a can of tomato juice to get the same result of adding water to tomato paste!
Tomato Sauce
1 small onion, peeled and very finely diced
1 or 2 cloves of garlic, peeled and finely chopped
1 tablespoon olive oil
1 x can of tomatoes (425g approx)
1 bay leaf
100 - 125 mls white wine
1/2 teaspoon vegetable bouillon
seasonings - salt and pepper to add on final tasting
Optional extras:
Pinch of Herbes de Provenance
A few fresh basil leaves - for Italian dishes such as meatballs with spaghetti
A pinch of chilli flakes for linguine with crab or lobster or spaghetti with meatballs
Method
Heat the oil in a pan and add the onion and sauté or cook without colouring for 5 minutes.
Add the garlic and cook for 2 minutes.
Raise the heat, add the wine and reduce until no liquid remains.
Add the tomatoes, bouillon and bay leaf. Reduce the heat, cover the pan and simmer VERY, VERY and in a covered pam, slowly for 30 minutes. If the mixture appears to stick add a little water.
Remove the bayleaf and process the mixture using a stick blender or liquidiser.
Taste and season and add additional ingredients to give an Italienne sauce (basil), chopped black olives to serve with chicken (Cacciatore) or to use to as the cooking medium for chicken pieces as in a casserole or add an anchovy filet or two to have a sauce on which one can oven cook a cod, marlin or salmon steak etc.
Tomato paste is added to sauces, such as Espagnole, for example, or tomato sauces etc., to intensify flavour, not reduced by adding water to give a sauce. Reducing the product by adding water is simply creating a hot tomato liquid and one which will be badly flavoured, IMHO! and not a sauce.
All the best,
Archiduc
Glad I could help. 
