Preheat oven to 350 degrees F. Lightly grease a 9×13" baking dish.
Make the brown butter herb breadcrumbs:
In a small skillet, melt butter over medium heat. Add sage & thyme. Cook 2-3 minutes, until butter browns and herbs begin to crisp. Add panko, stirring to coat in butter and herbs. Remove from heat and set aside.
Make Mac & Cheese:
In a medium pan, melt butter over medium heat. Add flour, whisking vigorously to reduce lumps. Cook for 1-2 minutes, stirring constantly, until golden brown. Add the garlic & cook 30 seconds, until fragrant.
Slowly add the milk & heavy cream into the pot, whisking constantly to eliminate any lumps. Cook 3-4 minutes, stirring occasionally, until the sauce has thickened to the point that it coats the back of a spoon. Add the pumpkin, fresh sage, ground mustard, ground nutmeg, & cayenne, stirring to combine (whisk if needed, to incorporate the pumpkin). Add shredded TomaProvence. Cook 1-2 minutes, stirring constantly, until the cheese is melted. Remove from heat. Taste & season with salt and ground black pepper, as desired.
In a large bowl, combine cooked macaroni and pumpkin cheese sauce, stirring to coat. Carefully transfer the pumpkin mac & cheese to the prepared baking dish. Top with the remaining brown butter herb breadcrumbs.
Cover with foil & bake for 25-30 minutes. Remove foil and bake 5-7 more minutes, until the breadcrumbs are toasty.
Serve immediately.
