How to Make It
Stir together first 6 ingredients in a small saucepan, and cook over medium-low heat, stirring constantly, 3 minutes or until butter melts. Cool about 15 minutes or until temperature reaches 110°.
Stir together yeast and next 2 ingredients; let stand 5 minutes.
Beat buttermilk mixture and yeast mixture at low speed with a heavy-duty electric stand mixer until blended. Add egg, and beat just until blended. Gradually add 4 cups flour, beating at low speed 4 to 6 minutes or until blended and dough is soft and smooth.
Turn dough out onto a lightly floured surface, and knead, adding up to 1/2 cup more flour, 1 Tbsp. at a time, as needed, until dough is smooth and elastic (about 5 minutes). Place dough in a large bowl coated with cooking spray, turning to grease top.
Cover and let rise in a warm place (80° to 85°), free from drafts, 1 hour or until doubled in bulk.
Stir together melted butter and rosemary. Punch dough down. Turn dough out onto floured surface, and roll into a 22- x 15-inch rectangle. Brush dough with half of butter mixture. (Keep remaining butter mixture at room temperature.)
Cut dough into 11 (2- x 15-inch) strips. Cut each strip into 5 (3- x 2-inch) rectangles. Make a crease across each rectangle by pressing lightly with a knife, and fold in half. Place rolls, 2 inches apart, on 2 parchment paper-lined baking sheets. Cover and let rise in a warm place (80° to 85°), free from drafts, 30 to 45 minutes or until doubled in bulk.
Preheat oven to 350°. Bake, uncovered, 15 to 18 minutes or until golden. Brush with remaining butter mixture, and serve immediately.