Prepare a .3 oz. (4-serving) box of sugar-free gelatin, according to the quick-set ice cube method. (Start with 1 cup boiling water, stir until gelatin is dissolved, then add 1 cup ice and stir). When heart shape cake is assembled, skim off top rounded portion of cake with a sharp serrated knife. Take one cup of the prepared gelatin mixture, and using a tablespoon, sprinkle over heart cake. Place cake in refrigerator until set. Mix topping ingredients until thoroughly combined. Frost cake; top with strawberries or spreadable fruit on top.