For the dough: Mix dry yeast with water. Add 6 tablespoons sugar to yeast. Cut buffer into flour. Add sour cream and eggs to yeast mixture and mix. Add yeast mixture to flour. Knead well. Divide into 4 parts and wrap in wax paper. Refrigerate overnight.

For the filling: Cream together cream cheese (at room temperature), egg yolks, vanilla, 9 tablespoons sugar, chopped pecans and crushed pineapple. Roll out dough into 4 rectangles. Spread cheese filling down center and lap each side over middle. Place on greased wax paper-lined cookie sheets. Cover and let rise 1 hour. Bake 25 minutes at 375°, or until light brown. Frost, if you desire.