Step 1

Combine balsamic vinegar, bourbon and Worcestershire sauce in a small bowl.

Step 2

Rinse and pat dry filet mignon and place in a shallow dish. Pour half of the marinade over the steaks (you'll use the other half with the mushrooms), turning to coat.

Step 3

Place in the refrigerator for an hour, turning after 30 minutes. (I cut the steaks in half horizontally to reduce cooking time.)

Step 4

Pre-heat oven to 425 degrees.

Step 5

In a cast iron skillet or other oven-proof pan, melt 2 tbsp butter over medium high heat.

Step 6

Place steaks in the skillet and allow to sear, untouched, 3 minutes. Discard the marinade in the dish the steaks were in.

Step 7

Turn steaks and remove from heat.

Step 8

Place the skillet in the oven for 15-20 minutes, depending on the thickness of the steak.

Step 9

While the steaks finish, melt remaining 2 tbs butter in a saute pan over medium heat.

Step 10

Add mushrooms and saute until soft, 5 minutes. Pour half of the remaining marinade over the mushrooms, add thyme, reduce heat and continue to saute 6-8 minutes.

Step 11

Taste at this point and add more marinade to the mushrooms, for a stronger flavor, if desired.

Step 12

Plate steaks when done. Spoon mushrooms over the top.