In a large mixing bowl, beat the softened cream cheese with the keto sweetener, vanilla extract, and lemon juice until smooth and creamy. Use an electric mixer for best results so there are no lumps — the mixture should become light and velvety as you whip it.

In a separate chilled bowl, whip the heavy cream until stiff peaks form. This aerates the cream and gives your cheesecake fluff its signature light, airy texture. Make sure the cream is cold and whip until it holds shape firmly.

Gently fold about half of the whipped cream into the cream cheese base using a rubber spatula. This initial fold lightens the mixture and makes it easier to combine the rest without deflating the air you just whipped in.

Carefully fold in the remaining whipped cream until fully incorporated and no white streaks remain. Once combined, spoon or pipe the fluff into individual serving bowls and chill for at least 30 minutes to set and develop flavor. Serve topped with fresh berries if desired.