Sprinkle powdered gelatin over the cold water. Set aside to allow gelatin to set.
Place 6 ramekins on a tray or baking pan (one that will fit in your refrigerator).
Cut strawberries into ¼" slices. Place 3 slices of strawberries into each ramekin.
Place remaining strawberries in a bowl and sprinkle with 2 tablespoons of sugar (this will macerate the strawberries and pull out some of the juices, resulting in a sugary syrup to pour over the panna cotta once unmolded).
Place cream, granulated sugar and vanilla bean paste in a large saucepan. Bring to a low boil over medium heat. Stir occasionally to avoid scorching the cream.
Remove from heat as soon as the cream begins to boil.
Add gelatin to the cream mixture and stir until the gelatin is completely dissolved. Allow to cool for 5 minutes.
Pour mixture into a heat-proof measuring cup and distribute evenly between the 6 ramekins pouring over the strawberry slices.
Place ramekins in the refrigerator for at least 3 hours to set.