01 - Beat cream cheese with hand mixer until smooth and fluffy.
02 - Add granulated sugar, lemon zest, lemon juice, and vanilla extract. Beat until well combined and creamy.
03 - In separate bowl, whip heavy cream and powdered sugar together until stiff peaks form.
04 - Gently fold whipped cream into lemon cheesecake mixture, followed by sour cream, until fully incorporated and light.
05 - Spoon mousse into individual serving glasses or bowls.
06 - Cover and refrigerate for at least 2 hours to set.
07 - Before serving, garnish with extra lemon zest, fresh berries, and crushed graham crackers if desired.