Mix butter with 3 cups of flour until well coated. Refrigerate until needed.
In a saucepan, heat half-and-half, sugar, and salt to 110 - 115 degrees (F). Add to yeast mixture. Beat until smooth. Beat in egg.
Roll out dough on a well-floured surface into a rectangle. Fold into thirds from the short edge and roll back into a large rectangle. Repeat 2 more times.
Roll dough into rectangle about 8 inches wide and 1/4 inch thick. Cut dough in half lengthwise to make two 4-inch wide strips. Refrigerate at least 3 hours or overnight.
Working with 1 piece of dough at a time, roll dough to about 8 inches wide. Use a spatula to spread the filling on each half of the dough. Roll dough over filling and cut each roll into equal size sections, usually 8 pieces total.
Place pastries seam-side down on a baking sheet. Make 4 cuts on one side of each pastry, extending at least 1inch into the pastry to create "fingers." Curve the pastry into a slight arch to separate the fingers. Cover tray loosely with plastic wrap and let rise for 1-1/2 to 2 hours, or until doubled in size.
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