Mix flour and butter-oleo as for pie
Add egg yolk and sour cream, mix well
Divide into 4 portions and wrap each, refrigerate overnight
Mix ground nuts, granulated sugar, and vanilla together, mix well and refrigerate
Roll each portion in sugar and flour to a 10 inch diameter
Cut into 16 pie pieces
Sprinkle with nut mixture
Roll like crescents
Bake at 350°F for 20 minutes on greased sheets