01 - Preheat oven to 400°F. Toss squash cubes with olive oil, salt, and pepper. Spread on a baking sheet and roast for 25–30 minutes until tender and caramelized. Let cool slightly.
02 - On a clean surface, mound flour and form a well. Add eggs and salt into the center. Gradually incorporate flour with hands until dough forms. Knead for 8–10 minutes until smooth and elastic. Wrap in plastic wrap and rest for 30 minutes.
03 - In a food processor, blend roasted squash, Parmesan, ricotta, nutmeg, salt, and pepper until smooth. Adjust seasoning to taste.
04 - Divide dough in half and roll each to about 1/16 inch thickness. Place teaspoons of filling 2 inches apart on one sheet. Brush edges with water, cover with second sheet, press to seal around filling, then cut into squares with a pastry cutter.
05 - Bring a large pot of salted water to a gentle boil. Add ravioli in batches and cook 3–4 minutes until they float to the surface.
06 - Melt butter in a skillet over medium heat. Add sage leaves and cook 2–3 minutes until butter is golden and fragrant.
07 - Remove ravioli with a slotted spoon and add to sage butter. Toss gently to coat evenly.
08 - Plate immediately and sprinkle with grated Parmesan cheese.