Melt the chocolate in a heatproof bowl over simmering water or in the microwave in 20-second intervals, stirring until smooth. Let cool slightly.

In a mixing bowl, whisk the eggs and sugar until pale and fluffy.

In another bowl, whip the heavy cream with vanilla extract until soft peaks form.

Gently fold the melted chocolate into the egg mixture.

Fold in the whipped cream in two additions, being careful not to deflate the mixture.

Spoon the mousse into serving cups and chill for at least 2 hours.

Serve with whipped cream, chocolate shavings, or fresh berries, if desired.

Alternate Instructions:

Melt chocolate and let it cool.

Whip cream until soft peaks form; set aside.

Whisk eggs and sugar until fluffy, then fold in chocolate.

Add whipped cream gently and chill in serving cups.

Garnish as desired and serve.