Prepare the cinnamon sugar: in a small bowl, mix together the coconut sugar and ground cinnamon. Set aside.
Add the oat flour, almond flour, maple syrup, melted coconut oil, vanilla, and salt to a mixing bowl. Mix until it forms a slightly sticky dough. If the mixture appears too dry, add a bit more maple syrup. If it's too sticky, add more oat flour.
Divide the dough into 5 pieces and keep them covered to prevent it from drying. Roll out one piece of dough into a rectangle of about 8x2-inch (1/16-inch-thick) on a piece of plastic wrap. Sprinkle about 3/4 tsp of the cinnamon sugar on top of the flattened dough, leaving about 1/2 inch on one side of the rectangle. Slightly press the sugar onto the dough to make it stick.
Use the plastic wrap to help you wrap the roll tightly into a long log. Be patient and roll it slowly. Press a little bit at the end to seal. Transfer to a plate or in a container and repeat with the remaining dough.
Transfer the logs to the freezer and freeze for 30 minutes before cutting each log into mini cinnamon rolls of about 1/2-inch thickness.
Mini cinnamon buns will keep for up to 2 months in the freezer. Enjoy straight from the freezer at a topping for ice cream, oatmeal, or just as a snack!