Bring water and salt to a boil in a large pasta pot and cook the ravioli according to package directions.
While the water is coming to a boil, cook, crumble and brown the sausage in a large skillet over medium-high heat (approximately 10 minutes).
Reduce the heat to the skillet to medium and add the butter, garlic, and canned pumpkin puree to the browned sausage along with the stock. Stir well to combine.
Add the grated nutmeg into the pumpkin and sausage sauce along with the Greek yogurt. Stir well.
Turn the heat off under the pan and add the vodka to the sauce. Stir well and simmer and turn the heat back to low under the skillet to keep warm.
Once cooked, drain the ravioli, reserving approximately ½ cup of the pasta cooking water. If desired add the reserved pasta cooking water to the skillet to thicken the pumpkin sauce.
Add the drained ravioli into the pumpkin sausage vodka sauce, or spoon the sauce over the drained pasta to serve.
Garnish with fresh sage leaves (optional) and a liberal sprinkling of Parmesan cheese.
Notes
Store any leftovers in an airtight container in the refrigerator for up to 5 days.May be frozen. Store the ravioli in an airtight freezer container or freezer bag. Label and date. Freeze for up to 3 months. Thaw in the refrigerator overnight.Reheat with ¼ cup water in a saucepan (covered) over medium heat, stirring occasionally on the stovetop, or heat in the microwave (covered) on medium power until hot.