If frosting still seems to thin to spread, add more coconut flour bit by bit as needed and continue to cool and thicken. (affairsofliving.com)
Try cutting back the coconut flour a bit next time, and adding them tablespoon by tablespoon just like you mentioned until you get that perfect consistency. (paleomg.com)
Add more white bread flour a bit at a time, stirring as you go, until the dough is too stiff to mix by hand. (sourdoughhome.com)