01 -
Mix sugar and cinnamon in a small bowl and set aside.
02 -
Cream butter, sugar, and salt. Add egg, milk, yeast, and flour. Mix until smooth, then fold in sprinkles. Let rise in warm place for 1½ hours.
03 -
Roll dough into 9x12-inch rectangle, spread with butter, sprinkle with cinnamon mixture and remaining sprinkles. Roll into cylinder and cut into 8 pieces.
04 -
Place rolls in buttered cast iron skillet, cover and refrigerate overnight. Next morning, let rise in warm place for 90 minutes.
05 -
Bake at 325°F for 32-34 minutes until golden. Cool 15 minutes, then top with glaze made from powdered sugar, milk, and vanilla. Sprinkle with additional sprinkles.