Place the low-fat cottage cheese in a blender or food processor and blend until completely smooth and creamy.
In a medium mixing bowl, combine the blended cottage cheese, part-skim ricotta, egg, sea salt, black pepper, and ground nutmeg until well incorporated.
Gently stir in the all-purpose flour until a soft, slightly tacky dough forms; avoid over-mixing to keep the gnocchi light.
Bring a large pot of water to a gentle simmer over medium-high heat.
Using two small spoons, scoop walnut-sized portions of the dough and carefully drop them into the simmering water.
Cook the gnocchi for 3-4 minutes, or until they float to the surface, then remove them with a slotted spoon and drain well.
In a large non-stick skillet over medium heat, melt the ghee and add the fresh sage leaves, cooking for 1 minute until the sage is crisp and the ghee is fragrant.
Add the cooked gnocchi to the skillet and toss gently for 1-2 minutes until they are lightly golden and coated in the sage butter.
Plate the gnocchi immediately and finish with a sprinkle of grated parmesan cheese.