In bowl of a stand mixer, add flour, potato flakes, yeast, sugar, salt, baking powder, powdered milk, butter, egg, and water.
Mix on low until ingredients start to combine, then on medium for 3 minutes. The mixture will be thick to start and then soften after a minute or so. The dough should be sticky and softer than regular roll dough, more like a sticky cookie dough.
If it is too dry (not sticky, easily handled, or crumbly), add a tablespoon or two of water.
Likewise, if it is too wet (more like banana bread, not able to be formed or handled at all in the next step), add a tablespoon or two of flour.
Divide the dough into 2 portions.
Coat your surface with additional gluten free flour, turn 1 portion of the dough out, then sprinkle more flour on top. Gently turn the dough to coat the outsides in a generous amount of flour so it isn't sticky, and roll out to a 12" circle. slice like a pizza into 8 sections, as if you were making crescent rolls.
Make cinnamon sugar by whisking together cinnamon, sugar, and vanilla.
Roll a marshmallow in melted butter, then in cinnamon sugar mixture, and place toward the wide end of a triangle of dough. Repeat with remaining triangles.
Fold the wide end of triangle over the marshmallow and roll toward the center, tucking edges as you do so. Gently form into a ball, rolling between your hands and tucking to be sure the edges are sealed as best you can.
Repeat with remaining dough and marshmallows.
Place rolls 4X4 into a well-greased 13"x9" baking pan, brush with melted butter and additional cinnamon sugar, and cover with plastic wrap.
Allow to rise in a warm place for 30-60 minutes. I use the rapid rise setting on my oven.
When rolls are almost doubled in size, bake in a preheated 350 degree oven for 25-30 minutes, until rolls are lightly brown (the color will vary based on what flour you use). The rolls should be hollow inside and not doughy at all.
Allow to cool for at least 15 minutes, then drizzle with glaze.