Preheat and prepare: Turn your oven to 375°F. Poke 3 medium sweet potatoes with a fork, put them on a sheet pan, and bake for 1 hour.
Rice the potatoes: When they're cool enough to touch, cut them open and scoop out the soft inside. Push it through your ricer into a big bowl.
Mix the dough: Add 2/3 cup drained ricotta, 1 egg yolk, 1/3 cup grated Parmesan, 1 teaspoon salt, 1/2 teaspoon pepper, and 1 cup flour. Mix it all together.
Adjust consistency: Sprinkle in 1/4 to 1/2 cup more flour, a little at a time. Stop when your dough feels soft and just a tiny bit sticky.
Roll and shape: Put some flour on your counter. Grab some dough, roll it into a rope about 1/2-inch thick, cut 1-inch pieces, and roll each down your fork.
Arrange gnocchi: Put your shaped gnocchi on a floured sheet pan. Keep them in one layer so they don't stick while you finish making the rest.
Boil water: Get a big pot of salty water boiling while you make the brown butter sauce in your skillet.
Make brown butter: Melt 1/2 cup butter in your big skillet over medium heat. Let it foam up, then watch for brown bits to appear. Swirl the pan gently.
Fry sage leaves: Drop 1/2 cup fresh sage leaves into the brown butter and let them fry for about 20 seconds. Pull them out with tongs and set aside.
Cook gnocchi batches: Work in batches. Drop some gnocchi in the boiling water and cook for 2-3 minutes until they float up. Scoop them out with your slotted spoon.
Finish and serve: Put your brown butter back on low heat. Add the cooked gnocchi and let the edges brown just a bit. Top with crispy sage and Parmesan. ENJOY!