Preheat oven to 350°F (175°C) and line a 9-inch springform pan or tart pan with parchment.
Mix crust: combine almond flour and erythritol; whisk egg, melted butter and vanilla, then stir into dry mix until a dough forms. Press firmly into pan.
Bake crust 10–12 minutes until light golden; cool completely.
Make topping: beat cream cheese until smooth; add Greek yogurt, sweetener, lemon juice and vanilla. Chill 10–15 minutes if too soft.
Spread topping evenly over cooled crust. Arrange berries on top and garnish with mint.
Chill at least 30 minutes before slicing. Slice with a sharp knife and serve cold.