If cooking them, use the whole lot and then sieve out the skin and pips after cooking. Some recipes call for skinned and de-seeded tomatoes. To prepare tomatoes in this way, use a sharp knife to ...
Blend the skinned tomatoes in a food processor and sieve to remove the seeds. Heat until the tomato pulp has reduced to a thick paste. Use in pasta sauces, casseroles and soups.
It is vital the onions are completely soft before the tomatoes are added. Slice the fresh or tinned tomatoes and add with the juice to the onions ... one wants to use the fondue as a vegetable ...