Soak the gelatin sheets in a bowl of cold water for about 5 minutes.

In a medium saucepan, combine the heavy cream, whole milk, and granulated sugar over medium heat. Split the vanilla pod and add it to the mixture (or use vanilla extract). Heat gently for around 5-7 minutes, stirring occasionally.

Remove the saucepan from heat and carefully add the softened gelatin to the warm cream mixture. Stir it gently until the gelatin is completely dissolved.

Strain the warm panna cotta mixture through a fine-mesh sieve into a clean bowl.

Dice the ripe mangoes into small pieces and evenly distribute them into your serving glasses.

Pour the panna cotta mixture gently over the diced mango in each serving glass, filling them about three-quarters full.

Cover each glass with cling wrap and refrigerate for at least 4 hours, or until set.

Whisk together the mango puree and fresh lime juice in a small bowl and layer the mango topping over each glass of set panna cotta.

Add a few fresh mint leaves on top just before serving.