Create a mound of the flour on a board and then fill the center well with the egg yolks, egg, oil and milk. Mix the eggs and gently knead and combine the flour to create a dough. Turn it and knead the mixture for at least 15 minutes, until you have a silky smooth dough. Let this dough rest for 30 minutes to 1 hour before putting it through a pasta machine.
Clean the squash (peel and seed) and cut into wedges - you should have 1.5 lbs. prepared weight. Roast with the butter, covered tightly with foil until completely soft and starting to brown. Uncover for the final minutes if it looks wet. Remove from the oven, leave to cool, then combine with the other ingredients, salt & pepper in a food processor. Work until smooth. Cool before using to fill the tortelli.
Roll the pasta to the desired thickness of just under 1 millimeter (0.7 millimeter if you're particular, the second thinnest setting on most machines), cut into 2.5 inch shapes (round or square, with straight or frilly edges) and put a dollop of filling in the center of each (1/4 oz or as much as you can fit and still be able to close the sides with a little room to spare. Mist lightly with water if the pasta is too dry to attach to itself. Fold in half (diagonally if you've cut squares), press to seal and twist around a finger (with the triangular or rounded flap pointing up, as with the finger), pressing the 2 long arms together to close.
Cook the tortelli in boiling, salted water for 2-3 minutes. Fry the butter and sage leaves until the butter carmelizes (turns a hazelnut-brown). Add a ladleful of pasta water and shake the pan. It will foam up and start to emulsify and thicken as you shake the pan. Remove the cooked tortelli from the water and add to the butter sauce. The pasta will continue to cook as the sauce thickens. The sauce is done when it coats the pasta like cream. Plate the tortelli, drizzle with Crown Maple Syrup and sprinkle with toasted hazelnuts.