In a mixing bowl, combine the gluten-free flour blend, xanthan gum (if needed), salt, sugar, and yeast.
In a separate bowl, whisk together the melted butter, warm milk, eggs, and vanilla extract.
Gradually add the wet ingredients to the dry ingredients, mixing until a dough forms. The dough will be slightly sticky.
Grease a bundt pan or a round cake pan.
In a small bowl, mix the granulated sugar and ground cinnamon for the coating.
Pinch off small pieces of dough and roll them into balls, about 1 inch in diameter.
Dip each ball into the melted butter, then roll it in the cinnamon-sugar mixture until coated.
Place the coated dough balls into the prepared pan, layering them evenly.
Cover the pan with a clean kitchen towel and let the dough rise in a warm place for about 30-45 minutes, until it doubles in size.