Add sugar to the juice, heat on the stove until the sugar dissolves, add instant gelatin, stir until it dissolves, remove from heat (do not bring to a boil!), strain.
To make this jelly, I used dessert jars. Pour the jelly into jars, let the jelly cool, put it in the refrigerator until it hardens (for 2-3 hours).
Then prepare a creamy chocolate mousse. Bring milk to a boil on the stove, remove from heat, add instant gelatin.
Stir until the gelatin dissolves, strain.
Add chocolate pieces to the milk with gelatin.
Stir the mass until a homogeneous mass is obtained (if the chocolate pieces have not melted yet, the mass can be heated a little on the stove, just the mass needs to be stirred constantly). Let the mass cool down.
Beat the sour cream well with a mixer.
Mix the whipped cream and chocolate mass.
Squeeze the creamy chocolate mousse onto the frozen jelly from the pastry syringe.