Mix flour, salt, sugar. Cut in butter. Moisten w/ sour cream, egg yolks. Knead until blended. Refrigerate overnight. Divide into 3 parts. Roll out and cut into 3 x 8 inch strips. Add 1 tbsp. filling. Roll like a cigar. Brush with 1 egg white mixed with 1 tbsp. water. Sprinkle with colored sugar. Bake at 400 degrees for 20 minutes.
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