To make filling: In a bowl, mix pumpkin, Cremona fruit in mustard syrup, parmesan cheese, crushed amaretti cookies, bread crumbs, nutmeg, salt, and brandy.
To make pasta: In a food processor, whirl 2 cups flour and salt to blend; add eggs and egg yolks, and whirl until dough holds together (or in a bowl, mix ingredients with a fork). Scrape pasta dough onto a lightly floured board and roll to coat with flour. Knead until dough feels smooth, adding flour as required to prevent sticking, about 1 minute if mixed in a food processor, 15 minutes if stirred. Cover dough with plastic wrap and let rest 10 to 15 minutes.
Divide dough in half and shape each portion into a smooth ball. Roll each ball through a pasta machine to 1/16 inch thick, or roll on a floured board. With a floured 2 3/4-inch round cutter, cut out 48 to 50 pasta rounds. Reroll dough as needed; discard excess.
Spoon an equal portion of filling onto center of each pasta round (about 1 teaspoon). Moisten pasta rims with water, fold over to enclose filling, and press edges with fork tines to seal. Arrange filled pasta on a floured surface (or 10- by 15-in. baking pans, if making ahead); let dry 10 minutes, turn over, and dry 20 minutes longer (or cover airtight and chill).
Bring 4 quarts water to a boil in a 7- to 8-quart pan over high heat; add half the pasta and cook, stirring occasionally, until tender to bite, 8 to 10 minutes. As they are cooked, transfer with a slotted spoon to a rimmed ovenproof platter; cover with foil and keep warm on an electric warming tray or in a 250° oven. Repeat to cook remaining pasta.
To make sauce: In an 8- to 10-inch nonstick frying pan over high heat, melt butter. Add sage leaves and stir often until darker green, about 30 seconds. Immediately, pour over the filled pasta, sprinkle with 1/2 cup parmesan cheese, and add salt and pepper to taste.