Bring a large pot of generously salted water to a rolling boil. Cook fettuccine until 1 minute shy of al dente (about 9 to 10 minutes). Before draining, ladle out 1/2 cup of starchy pasta water and set aside.

While pasta boils, melt butter in a wide skillet over medium heat. Add the fresh sage leaves in a single layer and fry for 2 to 3 minutes until crisp and darkened. Transfer crisp sage to a paper towel-lined plate using tongs, leaving the aromatic infused butter in the skillet.

In the same skillet, add olive oil, minced shallot, and garlic. Sauté for 1 to 2 minutes over medium-low heat until fragrant and translucent, being careful not to brown the garlic.

Stir in the pure pumpkin purée, vegetable broth, heavy cream, freshly grated nutmeg, cinnamon, sea salt, and black pepper. Whisk over medium-low heat for 3 to 4 minutes until sauce is smoothly incorporated and gently bubbling.

Fold in the grated Parmesan cheese and whisk until completely melted into a silky, luscious orange cream.

Transfer drained al dente fettuccine directly into the simmering sauce. Pour in a splash of reserved starchy pasta water and toss vigorously with kitchen tongs for 1 to 2 minutes over low heat until the sauce clings glossily to every ribbon.

Divide pasta into warm shallow bowls. Garnish immediately with crispy fried sage leaves, toasted chopped pecans, extra shaved parmesan, and fresh black pepper. Serve piping hot!