Heat the Cream:

In a saucepan, heat the heavy cream over medium heat until it begins to steam and small bubbles form around the edges. Do not let it boil.

Add Sugar and Chocolate:

Stir in the sugar and chopped chocolate. Continue stirring until the sugar is dissolved and the chocolate is fully melted, creating a smooth mixture.

Prepare the Gelatin:

Soften the gelatin sheets in cold water for about 5 minutes. Once softened, squeeze out any excess water.

Incorporate the Gelatin:

Add the softened gelatin to the warm chocolate mixture. Stir until the gelatin is completely dissolved. Make sure the mixture is warm but not boiling, as too much heat can affect the gelatin's setting ability.

Pour and Chill:

Pour the mixture into individual molds or serving glasses. Let it cool to room temperature, then refrigerate for at least 4 hours or overnight to set.

Serve:

Once set, serve the panna cotta with your choice of garnishes like fresh berries, mint leaves, or chopped nuts.