Place sweet potato chunks in a medium saucepan and cover with water. Bring to a boil over medium-high heat, then reduce heat to medium and allow to simmer 10-15 minutes until sweet potatoes are tender when pierced with a fork.
Drain sweet potatoes well and return to pot. Cover pot with lid and let sit offheat 10 minutes to allow sweet potatoes to dry out.
Once sweet potatoes have dried, run them through a ricer or food mill into a large bowl or finely mash with a fork in a large bowl. Let cool 20 minutes.
Very gently fold ricotta cheese, flour, and salt into cooled sweet potatoes until incorporated. Turn onto a floured surface and very gently knead until dough just comes together. (be careful not to overwork the dough)
Divide dough into four portions and roll each portion out into a 15 inch rope. (make sure to keep your surface well-floured) Cut ropes into 1-in pieces using a benchscraper or a sharp knife. Optionally, roll each gnocchi on the tines of a fork to get patterned effect. Transfer gnocchi to a large parchment paper-lined baking sheet.
Bring a medium pot of lightly-salted water to boil over medium-high heat, then reduce heat slightly to keep at a low simmer. Working in batches, drop gnocchi into boiling water and cook until gnocchi floats to the top, about 2-3 minutes. Carefully transfer gnocchi back to sheet pan with a slotted spoon and repeat cooking with remaining gnocchi batches.