Step 1

Heat a large cast iron skillet over high heat

Step 2

Generously salt and pepper the steak and sear it until it reaches medium rare (135°F on an instant read thermometer), depending on thickness about 3 minutes each side

Step 3

Let the steak rest for 5 minutes

Step 4

Slice the steak into strips, as thin as possible against the grain and set aside.In a medium sized saucepan set over medium heat, whisk the beef stock, dried thyme, salt, sherry, Worcestershire, garlic and onion powder, until fully combined

Step 5

Simmer for 5 minutes

Step 6

Butter the inside of the each of the french or hoagie rolls and sprinkle with garlic powder and place them open faced on a rimmed baking sheet

Step 7

Turn oven broiler on medium

Step 8

Quickly dip the strips of steak into the broth and place them in even amounts onto one side of each roll

Step 9

Sprinkle ⅓ cup cheese on each sandwich and arrange them open face on the baking sheet.Place the baking sheet under the broiler until cheese begins to melt, watching carefully for about 2 minutes

Step 10

Remove from oven and sprinkle with parsley if desired.In small cocottes or ramekins ladle ¾ cup serving of au jus into each container

Step 11

Serve au jus with the warm sandwich.