Butternut Squash and Sage Lasagna

Ingredients in this Recipe

1 1/4 cups homemade or store bought low sodium chicken stock
1 pound whole milk ricotta cheese
1/2 cup heavy cream
1/2 pound fresh mozzarella cheese, coarsely grated (2 cups)
1/3 cup loosely packed fresh sage leaves, coarsely chopped
2 large egg yolks
2 tablespoons extra virgin olive oil
2 tablespoons unsalted butter
3 1/2 pounds butternut squash, peeled, seeded, and cut into 1 inch pieces
4 ounces finely grated Parmesan cheese (1 1/4 cups)
Coarse salt and freshly ground pepper
Fresh Lasagna Noodles, (you will need only 1/2 of the batch), cut into 4 by 13 inch strips and cooked, or store bought dried noodles, cooked
Freshly grated nutmeg