1 c. semi-sweet chocolate chips
2 eggs
1 tbsp. sugar
1 c. very cold heavy cream
1 tsp. vanilla extract

Melt chips over hot water in double boiler. In large bowl, beat eggs with electric mixer. Start on low and turn up to high. When eggs start to get foamy, sprinkle in 1 tablespoon sugar. Keep beating, about 3 minutes, until eggs are thick and light in color. Scrape chocolate into beaten eggs with spatula.

Use mixer on low to blend the chocolate and eggs. Pour cream into a chilled mixing bowl. Add vanilla extract. Beat cream on high until very thick. Add about 1/4 of the whipped cream to the chocolate mixture. Lightly stir the cream into the chocolate mixture. Add about half of the rest of the whipped cream to the bowl.

Use the rubber spatula to fold the cream into the batter. Keep folding the batter gently over the whipped cream and turn the bowl until there are no streaks of white. Pour the mousse into serving bowls and chill at least 3 hours before serving. Top with remaining whipped cream.