Lightly grease 9 cups of a 12 (2 1/2-inch) cup muffin pan with cooking spray; set aside.
Roll dough into a 5x18-inch rectangle about 1/2-inch thick. Brush the surface with melted butter, reserving the remainder for topping the baked rolls.
Cut dough lengthwise into 5 equal strips, about 1-inch wide. Stack the strips, then cut crosswise into 9 equal pieces, about 2 inches wide.
Place each stack on its side in the prepared muffin cups. Cover loosely with greased plastic wrap and let stand until doubled in size, 30 to 40 minutes.
Preheat the oven to 375 degrees F (190 degrees C). Fill the empty muffin cups about halfway full with warm water.
Bake until the rolls are lightly golden brown, 15 to 17 minutes.
Brush warm rolls with remaining melted butter and sprinkle with flaky salt. Let stand for 5 minutes before removing from the pan. Recipe developed by Nicole Irwin
