For the Pasta:

1. 1. In a bowl, combine flour and salt. Create a well in the center and crack in the eggs. Mix until combined into a dough ball.
2. 2. Knead on a floured surface for about five minutes until smooth.
3. 3. Wrap in plastic and let rest for 30 minutes.

For the Filling:

1. 1. Preheat your oven to 400°F (200°C). Cut the butternut squash in half lengthwise, scoop out seeds, drizzle with olive oil, sprinkle with salt, and roast cut-side down on a baking sheet for about 30-40 minutes until tender.
2. 2. Once cooled, scoop the flesh into a bowl and mix with egg yolk, salt, and pepper until smooth.
3. Assembling the Ravioli:
4. 1. Roll out rested dough as thin as possible without tearing. Cut into squares or circles about three inches across.
5. 2. Place about one tablespoon of filling onto half of each square/circle of dough. Fold over and seal tightly by pressing down around edges.
6. Cooking the Ravioli:
7. 1. Bring salted water to boil in a large pot. Gently drop in ravioli and cook for about four minutes or until they float.
8. 2. Meanwhile, melt butter in a skillet over medium heat and add fresh sage leaves until fragrant.
9. Serve drizzled with sage butter sauce.