How to Make It
Stir together the gelatin and 2 cups water in a large bowl; let the mixture sit until the gelatin starts to firm up, about 3 minutes. Meanwhile, bring 4 cups of the juice to a boil in a medium pot. Add the hot juice to the gelatin and water mixture and stir until completely dissolved. Add the sugar, stir to dissolve, then add the remaining juice. Pour the entire mixture into a 10 ½-inch bundt pan. Refrigerate until set, about 6 hours. To unmold the jelly, fill a large bowl with hot water and lower the mold into it for 20 seconds, then invert onto a serving plate.