ok, here is a recipe for green tomato jam, not my MILs but it sounds close. you can sub any jello. sharet
green tomato jam
Ingredients
2-1/2 cups pureed green tomatoes (about 3 medium)
2 cups sugar
1 package (3 ounces) raspberry gelatin
Directions
In a large saucepan, bring tomatoes and sugar to a boil. Reduce heat; simmer, uncovered, for 20 minutes. Remove from the heat; stir in gelatin until dissolved. Skim off any foam. Pour into jars or freezer containers, leaving 1/2-in. head space. Cool before covering with lids. Refrigerate. Yield: about 3 cups.