Preheat oven to 350°F and spray a medium casserole dish with cooking spray and set aside.
Add the flour, baking powder, salt, sugar, and cinnamon to a large mixing bowl or stand mixer bowl and mix until combined.
Add the milk, vanilla, and egg yolk and mix just until combined.
While the mixer is running on slow speed, pour in the melted butter. Increase the speed to medium and beat until the butter is fully incorporated and the dough is pulling away from the sides of the bowl.
Flour a large surface area and shape the dough into a squarish ball. Let the dough rest for 10 minutes.
Roll out the dough into a large rectangle.
Mix together the filling ingredients and gently spread the mixture over the top of the dough.
Roll the dough tightly from the short end until fully rolled up.
Use unflavored dental floss to mark the dough into 8 even portions and then slide the dental floss under the dough and at each portion mark, cross the floss with your hands to cut through the dough.
Add the cut cinnamon rolls to the prepared baking dish and bake for 30 to 35 minutes. The tops of the rolls should be golden brown.
Whisk together the icing ingredients until smooth, then spread it over the top of the rolls while they're still warm.