Make the almond crumb: In a bowl, mix almond flour, melted butter, powdered sweetener, salt, and vanilla until it forms sandy crumbles. Taste and adjust sweetness. Set aside.
Whip the cream for the lemon layer: In a chilled bowl, whip 1/2 cup heavy cream to soft peaks.
Set aside.
Beat the lemon base: In another bowl, beat softened cream cheese with sweetener until smooth. Add lemon juice, zest, vanilla, and a pinch of salt. Beat until creamy and slightly fluffy.
Fold in the whipped cream: Gently fold the whipped cream into the lemon mixture until smooth and airy.
Do not overmix.
Make the whipped topping: Whip 3/4 cup heavy cream with sweetener and vanilla until soft to medium peaks. Chill until assembly.
Assemble the parfaits: In small glasses or jars, add a layer of almond crumb, then spoon in lemon cream, followed by a dollop of whipped cream. Repeat layers if your glasses are tall.
Chill: Refrigerate at least 1–2 hours to set and meld flavors.
Add garnishes just before serving.