Whisk together the gluten-free flour, granulated sugar, instant yeast, salt, and baking powder in the bowl of a stand mixer.

Add the warm milk, melted butter, egg, and apple cider vinegar to the dry mixture.

Using the paddle attachment, beat on medium-high speed for 4 minutes until the dough is smooth, thick, and slightly tacky.

Transfer the dough to a sheet of parchment paper lightly dusted with gluten-free flour and roll into a 12x15 inch rectangle.

Spread the 1/2 cup softened butter evenly across the dough, leaving a 1/2 inch border at the edges.

Mix the brown sugar and cinnamon in a small bowl, then sprinkle evenly over the buttered dough.

Using the parchment paper to assist, roll the dough tightly into a log starting from the long side.

Slice the log into 12 equal rounds using unflavored dental floss or a sharp serrated knife.

Place the rolls into a greased 9x13 inch baking pan, cover loosely with plastic wrap, and let rise in a warm spot for 60 minutes.

Preheat the oven to 350°F (175°C).

Bake for 22-25 minutes until the rolls are lightly golden and the internal temperature reaches 190°F.

Whisk the cream cheese, 1/4 cup softened butter, powdered sugar, vanilla, and 2 tablespoons milk until smooth.

Spread the frosting over the rolls while still warm to allow it to slightly melt into the layers.