Wash and scrub the unpeeled sweet potato, removing any undesirable areas. Pierce the potato a couple of times with a knife and cook in a microwave for 2 minutes. Use your fork to test it for doneness. If it’s still firm, cook in the microwave for another minute until the potato is tender. Once it’s cool enough to handle, chop it into large chunks and place them in a food processor along with the milk. Pulse until smooth.
Add mashed sweet potatoes, vegan butter, and brown sugar to a microwave-safe bowl (or use a saucepan over medium heat). Heat until mixture is warm to the touch (about 110F works here).
In a large bowl add the all-purpose flour, yeast, salt, cornstarch, and ground flax seeds. Stir to combine. Pour in the sweet potato mixture and stir to combine. Knead the dough in the bowl for 2 -3 minutes. Add 1 - 2 tablespoons of additional all-purpose flour as necessary to keep the dough from sticking too much. Spray the top with vegetable cooking spray, cover with a kitchen towel and set aside to rest, about 15 minutes.
Once the dough is ready, cover a working area with a sheet of plastic wrap. Place the dough on top of the plastic wrap and cover it with another sheet of plastic wrap. Use a rolling pin to roll the dough out to approximately 14X9 inches in size. It helps if you pull the top layer of plastic wrap off the dough and cover it again with the same sheet. It also helps to place a anti-slip pad to keep the dough from sliding as you roll it.
Combine the filling ingredients in a separate bowl. Pour this over the rolled dough, covering all of it except for about a half inch of the long edge furthest away from you. Starting from the long end closest to you, roll the dough until you're left with one long roll. Cut into 12 evenly sized rolls.
Prepare your baking dish by spraying a 9-inch round cake pan with nonstick cooking spray. Place rolls in prepared pan. Cover with a kitchen towel, and set aside to rise in warm, draft-free area until doubled in size, about one hour.
When the rolls have doubled in size, preheat oven to 375ᵒF. Place pan in a center rack and bake about 20 - 25 minutes until the rolls are golden in color.
While the rolls are baking, prepare the glaze. In a medium bowl, whisk together the powdered sugar and almond butter. Once combined add milk one tablespoon at a time until you reach a desired, spreadable consistency.
When the rolls are ready, remove them from the oven and allow to cool for about 10 minutes before adding the glaze. Serve warm.
Store cinnamon rolls in a sealed container in the fridge for up to 7 days. These can be frozen for up to 2 months. To serve, cook in the microwave until heated through.