In a small saucepan, combine the cream, sugar and milk. Sprinkle with gelatin; let stand for 1 minute. Heat over low heat, stirring until sugar and gelatin are completely dissolved. Stir in chocolate until melted.
Pour into eight 4-oz. ramekins coated with cooking spray. Cover and refrigerate for at least 5 hours or until set.
In a small saucepan, combine espresso and sugar. Bring to a boil; cook until liquid is thickened to a syrup consistency and reduced to about 1/4 cup. Unmold panna cotta onto dessert plates; drizzle each serving with 1-1/2 teaspoons syrup.