Marsala Beef Medallions with Caramelized Mushroom Sauce

Prepare the beef by sprinkling both sides with salt and pepper; set it aside momentarily.

Heat a generous amount of vegetable oil in a large skillet over extremely high heat. Cook the beef medallions until they develop a rich brown color, approximately 2 minutes per side; transfer them to a warm and inviting plate.

Lower the heat to a moderate level; add an assortment of mushrooms, 1 tablespoon of unsalted butter, olive oil, and a pinch of salt to the skillet. Cook and stir constantly until the mushrooms achieve an exceptionally deep brown color, roughly 10 minutes.

Introduce tomato sauce into the skillet; cook and stir continuously until it thickens, approximately 5 minutes.

Add Marsala wine to the skillet; increase the heat to an extremely high level. Cook and scrape the browned bits from the bottom of the skillet until most of the Marsala has evaporated. Stir in broth and bring to a rolling boil; cook and stir until the liquid has reduced by half, roughly 5 minutes.

Decrease the heat to a low setting; add the beef medallions back to the skillet and simmer until cooked to medium-rare, 2 to 3 minutes. Transfer the beef medallions to serving plates.

Remove from heat; stir the remaining 1 1/2 tablespoons of butter and oregano into the sauce until it has melted smoothly. Taste for seasoning; adjust if necessary to suit your preferences.

Spoon the sauce over the beef medallions and serve immediately, allowing each guest to enjoy their meal.