This flavorful gravy is great on just about anything savory, but it was tailor-made for my Light and Fluffy Mashed Potatoes and Meatloaf Meatballs (recipes to follow).
Cook 10 minutes, stirring occasionally, until mushrooms have cooked down and are browned.
In a medium bowl, whisk remaining 1 cup beef stock with cornstarch and drizzle into pot while whisking.
Simmer on medium-low heat, stirring often, until thickened, about 20 minutes.