Prepare Gelatin

If using powdered gelatin, sprinkle it evenly over 1/2 cup of cold milk in a small bowl. Let it sit for about 5 minutes to bloom. If using gelatin sheets, soak them in cold milk for about 5 minutes to soften.
2Heat Milk and Gelatin

In a saucepan, combine the remaining cup of milk with the bloomed gelatin (powdered or softened sheets) and cocoa powder. Stir over medium heat until the gelatin is fully dissolved and the mixture is smooth. Do not boil; heat gently until just warmed through.
3Pour into Molds

Remove the saucepan from heat. Pour the chocolate jelly mixture into empty milk cups or molds of your choice. Fill them to your desired level.
4Chill

Place the filled molds in the refrigerator and let them chill for at least 4 hours, or until set firm.
5Serve

Enjoy your sugar-free chocolate jelly! This creamy and delicious dessert is perfect for enjoying as a guilt-free treat anytime.