Copycat Olive Garden Beef Filets in Balsamic Sauce

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• Ready In: 30 mins
• Serves: 6

Ingredients

• 6 (6 ounce)  beef tenderloin fillets
• 4  tablespoons extra virgin olive oil
• 4  tablespoons butter
• 1  medium yellow onion, sliced thin
• 1  pinch salt
• 1  pinch black pepper
• 1⁄2 cup dry white wine
• 1⁄2 cup marsala wine
• 1⁄2 cup beef broth
• 2  tablespoons  balsamic vinegar
• 1  dash parsley, finely chopped
• 6  sprigs fresh rosemary

Directions

1. SAUCE: Heat oil and butter in a large saute pan over medium heat. Add sliced onions, salt, and pepper; cook 10 minutes or until softened and golden browned, stir frequently.
2. Add both wines, broth, vinegar and bring to a boil. Reduce heat and simmer for 10-15 minutes or until sauce is reduced by half.
3. BEEF: Lightly rub filets with oil; season with salt and pepper. Grill to preferred temperature. Place onions and sauce on a platter and top with steaks. Garnish with parsley and rosemary.