Preheat oven to 400°F (200°C). Toss the butternut squash with olive oil, salt, and pepper on a baking sheet. Roast for 30 minutes, or until tender.

While the squash is roasting, make the pasta dough. In a large bowl, mix flour and salt. Make a well in the center and add eggs and olive oil. Mix with a fork until a dough forms, then knead on a floured surface for 5-7 minutes, until smooth and elastic. Wrap in plastic wrap and let rest for 30 minutes.

In a small bowl, mash the roasted butternut squash with a fork. Mix in ricotta cheese, Parmesan cheese, nutmeg, salt, and pepper.

Roll out the pasta dough into thin sheets using a rolling pin or pasta maker.

Cut out small circles or squares of pasta dough.

Place a spoonful of the butternut squash filling in the center of each pasta circle or square.

Fold the dough over the filling and press the edges firmly to seal.

Bring a large pot of salted water to a boil. Add the ravioli and cook for 3-5 minutes, or until they float to the surface.

While the ravioli is cooking, melt butter in a skillet over medium heat. Add sage leaves and cook until the butter turns brown and smells nutty.

Drain the ravioli and add them to the skillet with the brown butter and sage. Toss gently to coat.

Serve immediately, garnished with additional Parmesan cheese and sage leaves (if desired).