Preheat the oven to 350F; lightly spray the inside of 9-inch cake pan with coconut oil.
For the dough, whisk together the almond flour, coconut flour, baking powder, stevia/erythritol blend, psyllium, salt, and fenugreek (if using) in a large bowl. Whisk together the foamy yeast, dissolved gelatin, vinegar, vanilla, eggs, egg yolks, and cream in a medium bowl. Add the wet ingredients to the dry and stir to combine. Let the dough rest for 3 minutes.
For the cinnamon filling, mix together all ingredients in a small bowl.
Oil your hands with coconut oil and shape the dough into a ball. Roll it out between 2 pieces of parchment paper into a rectangle approximately 14 inches long by 11 inches wide. Spread the cinnamon filling out onto the dough, leaving a border of about 1/4-inch all the way around. Roll the dough up into a log, wrap it in plastic wrap, and chill it in the freezer 10 minutes. Cut the log cross-wise into 9 equal pieces and arrange the rolls inside the prepared pan.
Bake until the rolls are golden, about 25 to 28 minutes. (Alternatively, you can cover the dough and refrigerate up to 2 days in advance before baking. If doing this, put the dough in the fridge to chill instead of the freezer, and bake it right from the fridge.)
While the cinnamon rolls cook, make the icing. Add the cream, butter, Swerve Confectioners, liquid stevia, and salt to a medium saucepan over medium heat. Bring to a boil and then turn the heat down and simmer until thickened, about 15 to 17 minutes, whisking occasionally. Remove from the heat and whisk in the vanilla. Cool to room temperature (it will thicken more as it cools), and then store it covered in the fridge for up to 5 days.
Frost the cinnamon rolls with the icing while they’re still warm and serve.