Combine the flour and salt in a mixing bowl. Whisk together the warm milk (no hotter than 110℉), sugar, vanilla extract, oil, and yeast in another bowl. Add the wet ingredients to the flour mixture while mixing to form a loose dough.

Turn onto a lightly floured counter and knead until a smooth dough forms - about 2-3 minutes of kneading. Shape into a smooth ball and let rise covered in a well-oiled bowl in a warm place for 1 hour - the dough should double in size.

Prepare muffin tin(s) or a large baking pan with non-stick cooking spray.

After 1 hour of rising, punch the dough down and roll out into a large rectangle, approximately 18 inches wide and 12 inches tall. Spread the softened butter all over the dough, avoiding the very top edge. Combine the brown sugar and cinnamon and sprinkle evenly over the buttered dough.

Roll the dough up tightly, starting from the long side of the rectangle. When you get to the end, pull the loose flap up over the roll and pinch the dough together to create a seam.

Slice into 18 rolls with a sharp knife. Place the rolls in the prepared muffin tin(s) or baking pan and cover with plastic wrap before refrigerating for 8-16 hours or overnight. *

Remove the cinnamon buns from the refrigerator and let rise in a warm place for 1 hour or until doubled in size. Preheat the oven to 350℉. Bake the risen cinnamon rolls in the preheated oven for 15-20 minutes or until golden. Let cool slightly for about 10 minutes before topping with the icing.

Whisk together the powdered sugar, vanilla, and 3-4 tablespoons of whipping cream. Drizzle over the slightly cooled cinnamon rolls. Serve immediately. Enjoy!