In a cast iron skillet over medium heat drizzle 1 tablespoon olive oil and swirl to coat. Sauté shallots until they soften and begin to brown. Remove from heat and set aside.

Butter 2 gratin pans. Preheat oven to 375°. In a small bowl, mix together pecans, Parmesan, bread crumbs, and remaining olive oil.

In a small frying pan, fry sage leaves in a small glug of olive oil, frying 20 seconds or so a side. Transfer to a paper towel-lined wire rack.

Melt butter in a saucepan over medium heat. When foaming subsides, add flour and whisk to combine. Continuously whisk roux until it turns a deep golden and takes on a nutty aroma, about 3 minutes.

Make the béchamel by adding both milk and cream, followed by nutmeg, cayenne, salt and pepper, and whisk to combine. Stir frequently until it bubbles slowly and thickens enough to coat the back of a spoon, about 8 minutes.

Add the pumpkin and whisk to incorporate. Add Gruyère, sage, and rosemary and fold together. Add the macaroni and stir all together, then spoon into the prepared gratin dishes.

Top with the bread crumb and toasted nut mixture and place onto a rimmed baking sheet. Bake 20-25 minutes or until golden and bubbling. Cool on a wire rack 10 minutes before serving.

Place gratin pans onto plates, top with the fried sage, and eat at once.