This is traditionally made in the fall when the first real frost is predicted and all the remaining tomatoes, ripe or not, are brought inside.    
Put through a food grinder (you can use food processor but a grinder gives a more even result):
24 med. green tomatoes, cored but not peeled
2 red sweet peppers 
4 green sweet peppers
8 small onions
Add:
4 Tbsp. salt
Mix well.  Let stand 2 hours.  Drain.  Squeeze out as much water as you can.
Heat:
2 cups sugar (up to 4 cups if you like sweeter relish)
3 cups vinegar
4 Tbsp. mustard seeds
2 Tbsp. celery seeds
Add tomato mixture; boil 10 minutes.  Pack boiling into hot (sterilized) jars, cap with hot (sterilized) lids, and hope they seal.  Unsealed jar(s) will keep all winter if refrigerated.
Makes about 10 1/2 pints.
From: Isa Reim, as told to Dorothy Huffman in the 1970s.
Versión en español: this post is also available in Spanish.
Esperanta traduko: this post is also available in Esperanto, because Dana is a language geek.
