3 cups prepared tomatoes (about 2 1/4 pounds ripe tomatoes 1 1/2 teaspoons grated lemon rind 1/4 cup lemon juice (2 lemons) 6 1/2 cups (2 pounds 14 ounces) granulated sugar 1 bottle pectin "Certo" (I think that's the 2 packages that come in the box nowadays, check with Certo if unsure)
First prepare tomatoes. Scald, peel, chop the fully ripe tomatoes. Bring to a boil and simmer 10 minutes.
Measure 3 cups of that into a large saucepan. Add the lemon rind and juice to the tomatoes. Add the exact measure of sugar and mix well. Bring to a full rolling boil and boil hard for 1 minute, stirring constantly. Remove from heat and add pectin. Skim off foam with metal spoon. Then stir and skim for 5 minutes to cool slightly and prevent floating "fruit."
Ladle into glass jars and you can use 1/8 inch of melted paraffin on top or use sealing lids.
