In a cold, large saucepan, add the olive oil and bacon, bring to medium heat and continuously sauté for about 8 minutes until browned and crispy. Remove bacon from pan and reserve bacon fat in the pan.
Reduce heat to medium-low, add butter and whole sage leaves and lightly fry sage until crisped and butter has browned, about 2 minutes. Remove sage from butter; reserve butter in pan.
Return pan to medium heat, add the garlic and crushed red pepper, sauté for 15 seconds, add pumpkin puree and cook for about 2 minutes.
Add the chicken stock and bring to medium-high heat, cook for about 90 seconds.
Add the heavy cream, reserved pasta water and season with salt and pepper. Whisk until well-incorporated and cook until sauce-like consistency and slightly thickened, about 90 seconds to 2 minutes.
Add the cooked pasta, pecorino and bacon, and toss until well-coated. Add the sliced sage and season to taste with additional salt and pepper, if needed.
Plate the pasta and top each serving with 2 to 3 fried sage leaves and more freshly grated pecorino.
