1 Tbsp lemon juice
4 C sugar
1 large box raspberry Jello
To make peeling the tomatoes easier, put 2 or 3 tomatoes in very hot water for about one minute so that the peel will just pull off:
The tomato peel will slip off easily at this point.
Take the hard core out of the peeled tomatoes (and the seeds if you want). You'll end up mainly using the outside flesh of the tomatoes. Dice the tomatoes. Stir together all ingredients but the Jello. Boil for 20 minutes. Take mixture off of the heat and stir in Jello. Stir until dissolved. Pour jam into hot jars and seal. Water bath them in boiling water (water should cover the tops of the jars by about 1 inch) for 15 minutes.