1 small package of lemon instant Jello
14-oz can of whole stewed or diced tomatoes
1 C boiling water
2 T vinegar
Pour boiling water into gelatin mix and stir for 2 minutes. Add tomatoes and vinegar. Stir and pour into a mold. Chill until firm. To serve, run warm water over mold until aspic releases, turn it upside down onto a platter, and slice like a cake.
You can add minced raw vegetables (peppers, onions, scallions) and herbs (chives, basil, thyme, rosemary) to this.
Instead of making one single aspic, you could also make individual ones. Then tuck a little surprise, like a cube of cream cheese, in the center of each one.