For the Gnocchi: Preheat the oven to 425 degrees F.
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.
For the Brown Butter sauce: While the gnocchi are cooking melt the butter in a large saute pan over medium heat. When the butter has melted add the sage leaves. Continue to cook, swirling the butter occasionally, until the foam subsides and the milk solids begin to brown.
Remove the pan from the heat. Stir in the cinnamon, maple syrup, salt, and pepper. Careful, the mixture will bubble up. Gently stir the mixture. When the bubbles subside, toss the cooked gnocchi in the brown butter.
Transfer the gnocchi to a serving dish and serve immediately.
