In a chilled mixing bowl, whip the heavy cream until stiff peaks form. Set aside.

In another bowl, beat the mascarpone cheese until smooth.

Add powdered sugar, lemon juice, lemon zest, vanilla extract, and salt to the mascarpone and beat until creamy and well combined.

Gently fold the whipped cream into the mascarpone mixture, being careful not to deflate the mousse.

Spoon or pipe the mousse into serving glasses or bowls.

Cover and refrigerate for at least 2 hours, or until fully chilled and set.

Garnish with fresh berries, mint leaves, or extra lemon zest before serving if desired.