Bake the sweet potatoes at 400F for approximately 1 hour until soft. Alternatively, poke holes in the potato with a knife and microwave for 5 minutes on each side until it pierces with a fork.
Take the peel off of the potatoes and add to a large bowl. Use a potato masher to finely mash the potatoes. Add the ricotta and salt and stir to combine.
Divide and roll into thirds, and cut into 1" gnocchi. Drop into boiling water, boil for 2-3 minutes or until the float to the surface. Remove and set on a clean plate, you may have to work in batches.
Heat the butter in a large skillet over medium high heat until bubbling. Add the gnocchi and pan fry until golden brown. Add the sage and pan fry for a few more minutes. Remove from heat and stir in the cream and parmesan.