Place sweet potato in a sauce pan with a little water and steam until soft enough to easily pierce with a fork - about 10 minutes
Remove sweet potato from pan and place on a plate
Place in the fridge for 1 hour until the sweet potato is completely cold
Smash the cold sweet potato with a potato masher or the back of a fork
Take 3/4 cup of the mashed sweet potato and place on a cutting board and shape into a ring (see chart below to see how you should do this)
Crack an egg into the center of the ring and whisk with a fork
Mix the sweet potato and egg together
Pour flour on top of the sweet potato and egg mixture
Mix flour into the egg and sweet potato and knead until a smooth, even dough ball remains ***If using all-purpose flour add 1/2 cup of flour to the mixture first and knead. Then, add 1/4 cup of flour at a time and continue kneading the dough until an even dough forms - you should use close to 1 cup of flour total***
Cut dough ball into quarters
Take one quarter and place on a floured cutting board
Roll into a long tube and cut 1" gnocchi pieces from the tube
Roll each piece on a pasta board or the back of a fork
Repeat this process until all 4 quarters of the dough are used
Boil salted water and add gnocchi to the boiling water
Once the gnocchi floats to the top it is cooked
Remove the gnocchi from the pot with a slotted spoon
Enjoy the gnocchi boiled or pan fry by heating butter or oil in a frying pan over medium heat and cook the gnocchi in batches until browned on all sides
Notes
If you want to freeze this dough for later I recommend freezing after you cut into gnocchi, but before you cook.