Preheat oven to 350°F. In a large mixing bowl, combine milk, panko, onion soup mix and salt. Allow to hydrate for 5 minutes. Spray muffin tin with non-stick spray.

Thoroughly mix ground beef into breadcrumb mixture; evenly fill each of the 12 muffin wells.

Place muffin tin on a sheet tray and bake 30 minutes or until the beef reaches an internal temperature of 160°F.

While meatloaves are baking, combine beef stock, ketchup, mustard and Worcestershire in a saucepan, bring to a simmer. Combine cornstarch and cold water, whisk into sauce mixture and simmer for 1 minute to thicken. Remove from heat and reserve sauce for glazing meatloaves.

Remove meatloaves from pan, glaze with sauce and serve.