Prepare the pasta dough and set out at room temperature to rest. On the stovetop, begin heating a stockpot of water to cook the ravioli., Place your measured canned pumpkin in a fine sieve, cover the top with plastic wrap, and weigh it down with another can or bottle. You want to drain excess moisture from the pumpkin, but not squish it through the sieve; about 15 to 20 minutes is sufficient., To make the pumpkin filling: In a medium-sized skillet melt the butter, and add the diced onion. Sauté until the onion becomes translucent., Add the turmeric and poultry seasoning. Cook for 1 more minute, until the spices are very fragrant. Add the drained pumpkin., Sauté the mixture until well combined and warmed through. This will cook out any excess moisture as well. Add the grated Parmesan cheese, and salt and pepper to taste., If the filling still seems a little loose, add 1 tablespoon of potato flour to bind it and make it smooth., Set the filling aside to cool to room temperature. The filling can be prepared the day before and refrigerated, wrapped in plastic, overnight. Return the filling to room temperature before stuffing and sealing the ravioli., To make the ravioli: Divide the filling into equal portions, based on how large you'll make your ravioli. A 2" circle pasta cutter will yield about 18 to 20 filled ravioli., Roll the pasta out by hand or with a pasta machine to the second thinnest setting. Place one sheet of pasta on the counter, and space dollops of filling about 2" apart on half the sheet. Whisk 1 large egg with 1 tablespoon cold water, and brush this egg wash around the filling., Fold the second half of the pasta sheet over the filling mounds. Press down around the filling to form a seal. Use a circle or square cutter to cut out each individual ravioli. Check the seal and crimp with a fork, if needed. Repeat with the remaining pasta and filling., Once all the ravioli are filled, cook in lightly boiling salted water (the water should taste like the ocean). Once the ravioli float, cook for another 2 minutes. Remove the pasta from the water with a hand strainer, place in a serving bowl and drizzle with melted butter or olive oil. Serve hot.