Preheat your oven to 350°F (175°C).
In a large mixing bowl, combine the flour, butter, sour cream, sugar, and salt. Mix until a dough forms.
Divide the dough into 4 equal portions and roll each portion into a thin circle.
Cut each circle into 8 wedges.
Place a spoonful of your desired filling at the wide end of each wedge.
Roll up each wedge starting from the wide end to form a crescent shape.
Place the kifli on a baking sheet lined with parchment paper.
Bake for about 20-25 minutes or until golden brown.
Let the kifli cool slightly before dusting with powdered sugar.
