In a small bowl, sprinkle the gelatin powder over the cold water and let it sit for about 5 minutes.

In a medium saucepan, combine the heavy cream, whole milk, sugar, and Earl Grey tea bags. Heat the mixture over medium heat until it reaches a gentle simmer.

Remove the tea bags and add the bloomed gelatin to the warm liquid. Stir vigorously for about 1-2 minutes until the gelatin is completely dissolved.

Remove the saucepan from heat and stir in the vanilla extract. Let the mixture cool slightly for about 10 minutes.

Carefully pour the cooled panna cotta mixture into serving glasses or molds. Place them in the refrigerator and let them chill for at least 4 hours.

When ready to serve, gently run a knife around the edges and invert onto plates. Garnish with fresh berries.