Preheat oven to 250 degrees
Season steaks with salt and pepper, to taste. Since this is steak au poivre, don't be skimpy with the pepper.
Place raw steaks on a lipped baking tray fit with a rack.
Insert a meat thermometer into the thickest part of one of the steaks.
Cook until internal temperature reaches 125 degrees (medium rare); mine took about 45 minutes.
Remove to a plate to rest for about 10 minutes.
Meanwhile prepare the sauce
In a small saucepan melt butter into the olive oil and add the minced onions. Cook for about 4-5 minutes or until onions become lightly golden.
Add thyme and peppercorns and cook for a minute more. Stir in dijon.
Turn off heat and add the brandy.
Return to heat and simmer until consistency thickens to about the texture of cream.
Then stir in the actual cream.
Season with salt, to taste and set aside briefly. Remove thyme stems.
To finish the steaks
Bring a cast iron pan to high heat with about 1 tablespoon of vegetable oil.
Sear steaks for 30-45 seconds per side; temperature should be hot enough that it shouldn't need longer than that to create a nice crust.
Immediately remove and serve steaks with peppercorn sauce spooned over the meat.