How to Make It
Lightly coat sides of pan with cooking spray.
MAKE THE DOUGH: Dissolve yeast in warm water in a large bowl; let stand 5 minutes. Stir in salt. Lightly spoon flour into dry measuring cups; level with a knife. Add 5 cups flour to yeast mixture; stir until a soft dough forms. Turn dough out onto a floured surface. Knead until smooth and elastic (about 8 minutes); add enough of remaining flour, 1 tablespoon at a time, to keep dough from sticking to hands.
Place dough in a large bowl coated with cooking spray, turning to coat top. Cover and let rise in a warm place (85°), free from drafts, 1 hour or until doubled in size. (Gently press two fingers into dough. If indentation remains, the dough has risen enough.) Punch dough down; cover and let rest 5 minutes.
Meanwhile, combine granulated sugar and cinnamon in a small bowl; set aside.
MAKE THE CUPCAKES: Roll dough into a 16 x 12-inch rectangle on a lightly floured surface; spread 2 tablespoons of softened butter over dough. Sprinkle with cinnamon-sugar mixture, leaving a 1/2-inch border. Roll up rectangle tightly, starting with long edge, pressing firmly to eliminate air pockets; pinch seam to seal (do not seal ends). Cut into 16 (1-inch-wide) slices. Place slices, cut sides up, in prepared pan (rolls will be crowded). Cover and let rise 30 minutes or until doubled in size.
Preheat oven to 375°.
Bake at 375° for 20 minutes or until rolls are light golden brown. Cool completely. Place a serving platter upside down on top of pan; invert onto platter.
MAKE THE GLAZE: Place powdered sugar and vanilla in a small bowl. Add 5 teaspoons milk, 1 teaspoon at a time, stirring to form a thick glaze. Drizzle about 1 teaspoon of glaze evenly over rolls. Sprinkle evenly with decorating sugars.