Add oil and butter to a large skillet and heat on high. Add ribeye and cook to desired doneness keeping in mind that it will cook a little more later in the recipe. Remove meat to a plate using a slotted spoon.

If needed add additional oil/butter but there should be a lot of liquid left behind from the meat. Add the shallots and mushrooms to the skillet and on medium heat with a lid on cook until vegetables are softened. Add garlic and cook for 30 seconds.

Add brandy to the skillet and ignite to cook off the alcohol. When flames die off add the beef broth, heavy cream, Worcestershire sauce, hot sauce, lemon juice, mustard, salt and pepper. Bring to a simmer to reduce the volume by half, about 5 minutes.

Add sour cream to the skillet and mix in. Heat for a couple of minutes and taste. Make any adjustments. If you need to thicken the sauce just bring it to a simmer for a few minutes. Add meat and any juices back to the skillet and mix into the sauce while heating.