In a small bowl, sprinkle gelatin powder over 1/4 cup cold water. Let it sit for 5-10 minutes to bloom and soften.

In a small saucepan, combine milk and honey. Heat over medium-low heat until warm and the honey has dissolved. Do not boil.

Remove the saucepan from heat. Add the bloomed gelatin to the warm milk mixture and stir until completely dissolved. Add vanilla extract and stir.

In a large bowl, whisk the Greek yogurt until smooth. Slowly pour the warm milk-gelatin mixture into the yogurt, whisking constantly until well combined and smooth.

Divide the panna cotta mixture evenly among four small ramekins or dessert glasses. Cover each with plastic wrap and refrigerate for at least 4 hours, or preferably overnight, until set.

To serve, you can dip the bottom of the ramekins in warm water for a few seconds to loosen, then invert onto serving plates. Garnish with fresh berries and chopped pistachios.