5 (1/4 oz.) packets unflavored gelatin
3/4 cups strained fresh orange juice, lemon juice or raspberry puree
1/2 cup superfine sugar, plus more for serving, if desired
Line an 8-by-5-inch loaf pan with foil. Brush it with oil and set aside.
Pour 1 cup water into a bowl; stir in gelatin and let it set for 5 minutes.
Heat juice and 1/2 cup sugar until sugar is dissolved.
Add softened gelatin and stir until melted.
Pour mixture into prepared pan. Let stand at room temperature or chill until firm, about 1 hour.
Unmold jelly unto a work surface and cut into 1-inch pieces with a large, sharp knife or mini cookie cutters.
If you like, roll jellies in more sugar just before serving.