Stir together the melted butter, brown sugar, and cinnamon for the swirl. Spoon the mixture into a zip-top bag and set aside for 10 minutes so it thickens enough to hold its shape.
In a large bowl, whisk together the flour, sugar, baking powder, baking soda, and salt.
Whisk the buttermilk, melted butter, and vanilla in a separate bowl. Pour into the dry ingredients and stir just until combined (small lumps are fine), then let the batter rest 5 minutes.
Make the glaze by beating the cream cheese until smooth, then beating in the powdered sugar, milk, and vanilla until silky and pourable.
Heat a griddle over medium-low heat and grease lightly. Pour 1/4 cup batter per pancake, and when bubbles form on the surface, snip a small corner off the bag and pipe a spiral of cinnamon mixture onto each pancake.
Flip carefully and cook 1 to 2 minutes more until golden. Wipe the pan clean between batches since the sugar can melt onto it.
Serve warm with the cream cheese glaze drizzled generously over the top, just like a fresh cinnamon roll in pancake form.
