Break the chocolate into pieces (if you don't use the chocolate chips) and place into a bowl.
In a small saucepan, heat the whipping cream until simmering. Pour the simmering cream over the chocolate and mix until smooth and evenly melted.
Add vanilla and stir. Let cool 15 minutes.
Meanwhile, in a small bowl, sprinkle gelatin over 4 tablespoons cold water and mix well. Add 4 tablespoons boiling water and stir constantly until completely dissolved.
Add the dissolved gelatin to slightly cooled chocolate-cream mixture and mix well. Spoon the white chocolate mousse into 4 serving cups and refrigerate until set.