**Prepare the Dough**: Warm the milk, then mix it with yeast and sugar in a stand mixer. Add melted butter, vanilla, and eggs, then gradually add flour and salt. Let the mixer knead the dough for 5 minutes. If you don't have a mixer, knead by hand. Let the dough rise in a greased bowl in a warm place for an hour.
**Prep the Pan**: Line a 9-inch springform pan with parchment paper.
**Make the Filling**: Mix softened butter, brown sugar, cinnamon, vanilla, and salt in a bowl.
**Assembly**: Roll out the risen dough into a rectangle on a floured surface. Spread the filling over it, leaving a border. Cut the dough into strips, then roll each strip into a cinnamon roll shape. Place them in the prepared pan, cover with plastic wrap, and let rise for 30 minutes while preheating the oven to 350°F.
**Bake and Frost**: Remove the plastic wrap and bake the cake for 35 minutes until golden brown. Let it cool completely before removing from the pan. For the frosting, beat butter and cream cheese until smooth, then add vanilla, powdered sugar, salt, and cream/milk until smooth. Spread over the cooled cake and enjoy!