The idea of making tomato jam may seem odd at first, but tomatoes are, after all, a fruit. They have a lot of natural sugar and pectin; add the right spices and you have a sweet-spicy condiment that's terrific on sandwiches, with cheese and crackers (including goat cheese or cream cheese), and even on toast for a savory/sweet switch-up with your usual strawberry.
If you are looking for something to do with your summer glut of summer tomatoes, this is a good choice. Every time I make it I give away several jars and it's always a hit.
More than a few years ago, I picked up this recipe from Mark Bittman's old The New York Times column, and there was even one of the entertaining videos he did periodically.
Bittman does not call for peeling the tomatoes, but I do; the skins don't really break down and I don't care for those chewy bits in my jam. Some people would go so far as to seed the tomatoes, but the seeds don't bother me. Besides, it's been shown that a lot of the strongest flavor components come from the "jelly" around the seeds, and if you remove the seeds, you'll wind up removing a lot of the jelly. So, seeds in; skin out.