Spinach Mushroom Tortellini Soup

unsalted butter

extra-virgin olive oil

cremini mushrooms, quartered or sliced

yellow onion, chopped

garlic, minced

fresh thyme, stems removed

dried sage

red pepper flakes

nutmeg

all-purpose flour

white wine

cartons vegetable or low-sodium chicken broth

cheese tortellini (or spinach or meat)

parmesan cheese, grated, plus more for garnish

fresh spinach, roughly chopped

half-and-half

kosher salt and freshly ground pepper,