Step 1

Preheat oven to 450 degrees F.

Step 2

Place squash on a baking sheet and roast until soft 30 to 40 minutes. Scoop out flesh and run though a food mill. Place the puree into a medium saucepan and cook over low heat until almost dry. Add the remaining ingredients and season with salt and pepper to taste. Lay a sheet of pasta dough on a lightly floured work surface and distribute a heaping teaspoon-sized portion of the filling at least 2 inches apart. Use your fingertip or a brush to moisten the edges of the pasta sheet with the egg wash. Carefully place a second sheet of the pasta dough on top of the first and press with your fingertips to separate the rows of filling. Repeat with the remaining dough. With a ravioli cutter or pastry wheel, cut along straight lines on the vertical and horizontal to form each ravioli square. Press the edges closed with your fingertips to seal well. Bring a large pot of salted water to a boil. Carefully drop in the ravioli and cook for about 5 minutes. Drain, plate and spoon butter sauce over and garnish with finely chopped chives.

Step 3

Melt butter in a medium saute pan over medium heat and cook until the foam subsides and the butter begins to brown, 3 to 4 minutes. Remove from the heat, stir in the hazelnuts and sage and season with salt and pepper to taste.