Pierce the sweet potato with a fork. Bake the sweet potatoes until tender and fully cooked, between 40 to 55 minutes depending on size. Cool slightly. Cut in half and scoop the flesh into a large bowl. Mash the sweet potatoes and transfer to a large measuring cup to make sure the sweet potatoes measure about 2 cups. Transfer the mashed sweet potatoes back to the large bowl. Add the ricotta cheese, salt, cinnamon, and pepper and blend until well mixed. Add the flour, 1/2 cup at a time until a soft dough forms. Lightly flour a work surface and place the dough in a ball on the work surface. Divide the dough into 6 equal balls. Roll out each ball into a 1-inch wide rope. Cut each rope into 1-inch pieces. Roll the gnocchi over the tines of a fork. Transfer the formed gnocchi to a large baking sheet. Continue with the remaining gnocchi.
Meanwhile, bring a large pot of salted water to a boil over high heat. Add the gnocchi in 3 batches and cook until tender but still firm to the bite, stirring occasionally, about 5 to 6 minutes. Drain the gnocchi using a slotted spoon onto a baking sheet. Tent with foil to keep warm and continue with the remaining gnocchi.