How to Make It
Bring a small pot of salted water to a boil. Using a sharp paring knife, score an “X” on the bottoms of the tomatoes and blanch for 30 seconds; drain. Slip off the skins and halve the tomatoes crosswise. Remove the seeds and coarsely chop the tomatoes.
In another pot, combine the vinegar with the sugar and cook over moderate heat, stirring, until the sugar is dissolved. Add the tomatoes, garlic and ginger and cook over moderate heat for 5 minutes. Season with salt and pepper.
Working over a clean saucepan, pass the tomato mixture through a sieve, pressing on the solids. Bring to a boil. Add the pectin per the package instructions and boil for 1 minute.
Funnel the hot jelly into hot, sterilized jars, leaving about 1/4 inch of room on top. Screw on the lids securely. Using canning tongs, carefully lower the jars onto a rack set in a pot of boiling water, making sure they are covered by at least 1 inch of water. Boil for 15 minutes, then transfer the jars to a rack to cool completely. Refrigerate until the jelly is set, at least 12 hours.