Begin by softening the cream cheese.

In a mixing bowl, combine the softened cream cheese and powdered sugar. Beat until fluffy, about 2 minutes.

Stir in the vanilla extract and lemon juice, if using.

In a separate bowl, whip the heavy cream until stiff peaks form.

Gently fold the whipped cream into the cream cheese mixture.

Transfer the mousse into serving cups and refrigerate for at least 2 hours.

Once chilled, serve the mousse cold.