Preheat your oven to 400 degrees F.Poke a few holes in the sweet potatoes and bake for 45 minutes or until soft and tender. When the sweet potatoes are cooked, slice them in half, allow to cool, and finely mash or puree them. In a large bowl, mix together the sweet potatoes, ricotta, egg, salt, and flour. Stir the mixture until just combined. If the dough seems wet, add a tablespoon of flour at a time until it can be formed into a ball. The dough should be sticky.Generously flour a clean counter and scrape the dough out onto the counter. Cut the dough into four equal pieces. Working with one piece of dough at a time, roll the dough into a rope about 1 inch thick and cut into bite size pieces. Repeat this process with the other pieces of dough and place the gnocchi on a baking sheet that has been dusted with flour. At this point, the gnocchi can be kept, covered in the fridge for up to 1 day and then boiled just before you are ready to eat.To make the sauce. Heat the butter in a large skillet over medium-high heat and cook until it begins to brown, about 3-5 minutes. Stir in the rosemary and then slowly pour in the cream. Whisk in the parmesan, nutmeg, cayenne, and season with salt and pepper. Simmer the sauce for 3-5 minutes, whisking until smooth. Keep warm over low heat. Bring a large pot of salted water to a boil. Boil the gnocchi until they float to the top and are cooked through, about 3-4 minutes. Remove the gnocchi using a slotted spoon or spider strainer and drop it right into the sauce, gently tossing to combine. If the sauce thickens up, add a splash of the gnocchi cooking water to thin it a bit. Divide the gnocchi among bowls. Top with rosemary and parmesan, of desired. EAT!