In a small bowl, combine the ½ cup of canned coconut milk with the 2 teaspoons of gelatin. Stir gently to combine and let it sit for about 5 minutes.
In a small saucepan over low heat, combine the chopped dark chocolate and 1 cup of canned coconut milk. Stir frequently until the chocolate is completely melted and the mixture is smooth. Remove from heat.
Add the bloomed gelatin mixture to the warm chocolate and coconut milk mixture. Stir well until the gelatin is fully dissolved.
Stir in the espresso powder and vanilla extract, ensuring that everything is well incorporated.
Carefully pour the mixture into your prepared ramekins or dessert cups, filling them about three-quarters full.
Cover the ramekins with plastic wrap and refrigerate for at least 4 hours or until the panna cotta is fully set.
Once set, gently run a knife around the edge of the panna cotta to loosen it. Invert onto a plate if desired, or serve directly in the ramekin.