Preheat your oven to 400°F (200°C) and grease a 9x13-inch baking dish.

Bring a large pot of salted water to a boil, add pasta and cook until al dente, about 7-8 minutes. Drain and rinse.

Cook diced bacon in a Dutch oven over medium-low heat until crispy, about 8-10 minutes. Remove and set aside.

In the same pot with bacon fat, melt butter and toast panko breadcrumbs until golden brown, about 3-5 minutes. Set aside.

Sauté shallots and sage in the remaining butter until shallots are translucent, about 3-4 minutes.

Sprinkle flour into the shallots mixture, stirring for 1-2 minutes, then whisk in half and half and pumpkin puree until smooth. Simmer for 5 minutes.

Fold in cheddar and gruyere cheese until melted, then mix in the cooked pasta and half of the crispy bacon.

Pour into the baking dish, top with toasted breadcrumbs and remaining bacon.

Cover with foil and bake for 15 minutes. Remove foil and bake for another 5-10 minutes until bubbly and golden.