01 - In a large mixing bowl, combine mascarpone cheese, lemon zest, lemon juice, sugar, and vanilla extract. Beat with hand mixer on medium speed until smooth and well combined.
02 - In a separate bowl, whip heavy cream to stiff peaks using hand mixer or stand mixer.
03 - Gently fold whipped cream into mascarpone mixture in two additions using spatula until fully incorporated and light.
04 - Spoon or pipe mousse evenly into serving glasses or bowls.
05 - Cover and refrigerate for at least 2 hours or until set and chilled.
06 - Garnish with fresh berries, sprinkle of lemon zest, and mint leaves just before serving if desired.