Step 1

Rub tenderloin filets with steak seasoning and place in a cast iron skillet (ad) with 1 Tbsp. olive oil.

Step 2

Sear filets over medium high heat on all sides.

Step 3

Place filets in a 400 degree oven for 3 to 5 minutes until cooked to desired temperature.

Step 4

Check frequently.

Step 5

Remove filets from oven.  Spoon marsala sauce over filets and cover with foil until ready to serve.

Step 6

Melt butter in skillet (ad) over medium heat.  Add onion and sauté until tender.

Step 7

Add garlic and mushrooms.  Sauté for 3 minutes.

Step 8

Add marsala wine, teriyaki sauce, beef stock and pepper.  Cook until mushrooms are tender (about 10 minutes).

Step 9

Mix flour with a little water and add to skillet.  Stir over medium heat until thickened.

Step 10

Add heavy cream and stir for 2 minutes over low heat.

Step 11

Spoon mushroom marsala sauce over filets and mashed potatoes to serve.