01 - Process ricotta cheese in a food processor until exceptionally smooth, approximately 1 to 2 minutes.
02 - Gently melt the chopped dark chocolate using a double boiler or in the microwave (in 20-second intervals), stirring until completely smooth. Allow to cool slightly.
03 - Add the cooled melted chocolate, granulated sugar, and vanilla extract to the processed ricotta. Blend until thoroughly incorporated and a creamy consistency is achieved.
04 - In a separate bowl, whip the cold heavy cream to soft peaks.
05 - Delicately fold the whipped cream into the chocolate-ricotta mixture until no streaks are visible.
06 - Divide the mousse evenly among 4 serving glasses or bowls.
07 - Refrigerate for a minimum of 2 hours, or until the mousse is set.
08 - Prior to serving, optionally garnish with shaved chocolate, fresh berries, or mint leaves.